Landracing Forum
Bonneville Salt Flats Discussion => Build Diaries => Topic started by: entropy on October 28, 2013, 06:18:23 AM
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Houston Partners:
Don is a career pilot with extensive powerplant & airframe experience/knowledge.
Karl has strong back, weak mind, Founder of TFA, retired w/lots of time, i love spreadsheets & roadtrips & short walks to my car.
2012 Karl & Don retired from MC LSR (asphalt & some salt), noobs to cars on salt.
26-Jul-13 Don called Karl and broached the idea of starting up a "Lakester Project". Karl jumped at the idea :-D
Aug-Sept Several good candidates, alot of help from KiwiPaul, Stainless, Joe Timney, Sparky, Scott Horner, Sumner, others
23-Sep-13 Stainless sent KDG a link to a V-8 bellytank lakester, beautiful work in 2007/2009, but never run
http://www.landracing.com/forum/index.php/topic,3011.0.html
sept, 2023 detailed advice from Tom Burkland, Rex Svoboda, others
27-Sep-13 KDG flew to SLC, a BUNCH of advice from Tom Burkland.
28-sep-13 Karl drove to Missoula (i didn't know they had airports in Montana????), met with Owner Chuck and Rex. B Lakester is done, motor running, looks great but never thru tech. Cabin too short for Karl or Don (TFA charter members), but fixable.
30-Sep-13 Don & KDG met for 3.5 hrs, did "plus-delta" of blue CC in Dallas vs Chuck's car, very thorough analysis, Chuck's car won if we can make a deal. We subsequently made a deal. Chuck is GREAT to work with!
26-Oct-13 car delivered to Pearland, Texas
(http://i206.photobucket.com/albums/bb194/guntekd/131026-openingtrailer_zps81df483e.jpg)
Don's wife Krys, Don, Karl, Karl's wife Helena celebrating.
(http://i206.photobucket.com/albums/bb194/guntekd/131026-DampKampwivestoastingcloser_zps3374c170.jpg)
Karl's wife Helena is a perfect fit in the cabin!
(http://i206.photobucket.com/albums/bb194/guntekd/131026-smilinghelenaincockpit_zps93a9b65e.jpg)
TFA Charter member Don doesn't fit as well as Helena
(http://i206.photobucket.com/albums/bb194/guntekd/131026-Donincar_zpsd20175dc.jpg)
Karl's daughter Jessie making motor sounds
(http://i206.photobucket.com/albums/bb194/guntekd/131026-jessiemakingmotorsounds_zps71bb1fdd.jpg)
Car going into it's new home/rehab facility
(http://i206.photobucket.com/albums/bb194/guntekd/131026-driverampAlpushingcarintohanger_zps5a4e9a6c.jpg)
Basically we plan to make whatever safety & reliability mods are necessary:
1. To arrive at a state of "no compromise" safety & handling (yes, Tom Burkland has been talking to us :-D).
2. For Don & I to be comfortable in the cage / cabin
3. Tweak lil stuff to assure adherance to current rules
4. Add data logging
5. Other stuff
Our objective is to have a fully functional, reliable, safe car for Don & Karl to license/run at Speed Week, 2014.
We are not concerned about hp (yet... :-D)
I gotta say Slim's Site and it's members are 110% AWESOME!
The outpouring of help as we looked for a car and considered mods has been unbelieveable.
I love the great MC people, forums, events, but it seems the salt/car guys take this to another level.
Thanks to everybody!
(does anyone know what Tom Burkland's typing speed is?)
Karl
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That's a really neat project. It looks beautiful. I wish you all a lot of excitement and fun with it. Judging by the size of all drivers concerned it looks like you have real candidates on the female side. :-D
The forum is great and like you say the people are special. Welcome. Mike.
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The fun begins...
Looks like you have quite a few driver options, and a few safety changes to make.
Think about adjustable pedal sets...
The car looks good in Texas... is that the right shade of orange? :evil:
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I couldn't be happier for you & Don, congrats Karl. I know you will do it right, and go fast.
I hope to see you at Speed Week next summer, with a modifed version of your old bike. What goes around, comes around. :cheers:
Dean
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I couldn't be happier for you & Don, congrats Karl. I know you will do it right, and go fast.
I hope to see you at Speed Week next summer, with a modifed version of your old bike. What goes around, comes around. :cheers:
Dean
+1000!!
Looks great Karl! I know you and Don will be going fast in no time!!
Like Dean I hope to see you at speedweek with ole RBR. It will be a regular family reunion! :cheers:
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Just remember being front wheel drive it will steer a little different.
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Speaking for myself and I am sure many others on this forum I am so pleased that this very well built lakester has found a good home and will be making big noise at the Salt next year. Looking forward to seeing on the Salt and talking with all of you.
Rex
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I agree with Rex! Glad to see it found a good home.
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Thanks, everybody!
I am very anxious to join Don as he scales the car(hopefully) this week, but wifey & I are driving up to Delaware to get a taste of the Punkin Chunkin Festival with a bunch of my wife's kinfolk. We'll stop and see Joe & Donna Timney tomorrow afternoon.
Good times, BUT I want to get my hands on the car, yup.
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A lil update:
TFA Racing is making strong progress thank's to Don's fabrication abilities!
The frame has been extended by 22" (16" to cabin and 6" to engine bay).
New seat/seat mounts and all new harness/anchors. This is tricky stuff.
Relocated rear axle 13.5" aft, and added longitudinal and vertical adjustment; old axle soon = toast.
Old WB = 110", new WB = 145.5".
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1554_zpse372085c.jpg)
Added hand/arm protection bars to the cabin, will add plates inside cabin to protect driver from bare tubing.
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1597_zps7a877534.jpg)
The extra 16" allows Don or I (both 6'3") to fit very comfortably in the cabin.
Still need to add interior plates and helmet padding.
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1602_zpsd772e693.jpg)
Yesterday we added two x 2.0"(viewable) x 0.5" thick Lexan windows in the firewall for fire detection.
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1608_zpsa81498fc.jpg)
Next, Don is taking aim at the skin, both to cover the extended chassis and to give much better motor access.
All new windshield & canopy with associated hinges & latching mechanism is in the works.
We have received a BUNCH of advice from many members of this forum.
There are a couple of guys who have given us tireless, detailed thoughts & suggestions, but I'm not going to mention Tom Burkland and & Rex Svoboda by name.
Thanks to everyone, this project is coming along nicely.
I am especially proud of Don and "our" fabrication results to date; I only wish I could help him more.
Karl
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TFA Racing is making great progress thanks to my partner Don's high level design & fabrication skills and stick-to-it work habit.
The canopy frame, 1/4" Lexan windshield, canopy hinge, supports, locking mechanism, and hat are "90% done, only 90% to go". The windshield skirt is next on the hit list, along with the hood. The sleek new canopy/windshield REALLY changes the look of the car, we love it. THANKS Don!
Current focus is ASAP completion of "all" the required welding on the chassis, because on May 12, I will bring it to the Powdercoating guy for blasting & white pc.
On the logistics side, while Don was fabricating I drove to Pearl Mississippi and brought back our "new" Y2000 30' Pace Shadow GT enclosed trailer. We will extend the internal ramps to accomodate our 145" wheelbase, check brakes & bearings, etc, but it is in very good shape overall, tows straight as an arrow in heavy sidewinds at the 80mph permitted in East Texas. The rented powerstroke F350 got better mileage at 65mph...
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1994_zpsc89ddd0f.jpg)
Another major issue has been getting wheels with 1 5/16" offset (gives zero scrub). That seems to have been accomplished through the help of Allied Wheels in LA. Greg Mulkey took interest in our project and suggested aluminum with steel lug inserts. He recently turned out a beautiful pilot wheel, stout as heck, which measures up just fine. He is now making 5 more.
Karl
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1784_zpsfe992b67.jpg)
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Awesome. :cheers:
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Looking awesome karl ! Your 2 wheel friend ,jeff! :cheers:
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Looking awesome karl ! Your 2 wheel friend ,jeff! :cheers:
hey Jeff, I hated missing seeing you at Mojave.
Maybe you should make a trip to Bonneville?
Karl
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Very cool guys!
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Sound good karl ! Speedweek? I'll be bub's motorcycle speed trails for sure ,love to cheer you guys on& ckeck on the new hot rod !
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Looks great Karl & Don. That new windscreen looks swanky, is it cracked?
3 months to go, yikes!
Dean
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Looks great Karl & Don. That new windscreen looks swanky, is it cracked?
3 months to go, yikes!
Dean
Thanks, dean!
I am sure you are joking about the crack, yes? :cheers:
karl
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I'm not, but I guess it's just the rippling of a protective film. Shape looks better to my novice eye.
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1994_zpsc89ddd0f.jpg)
Here's greenie as of this weekend, hopefully start wiring the Motec soon.
(https://farm8.staticflickr.com/7190/14064925794_c30f957a1e_z.jpg)
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I'm not, but I guess it's just the rippling of a protective film. Shape looks better to my novice eye.
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_1994_zpsc89ddd0f.jpg)
Here's greenie as of this weekend, hopefully start wiring the Motec soon.
(https://farm8.staticflickr.com/7190/14064925794_c30f957a1e_z.jpg)
Dean,
I REALLY like seeing bars ahead of the fork tubes on greenie, puts yr arms in a much better position. When are you gonna run it? where?
On Lexan cracking, i'm no expert but i gotta tell you it is a world better to play with than plexiglass. It seems to have mechanical properties more like a soft metal than plastic. It can be bent like crazy and drilled like aluminum, although it apparently takes heat to bend it permanently. It doesn't seem to easily crack. (i'll probably eat those words). As you note, the "cracks" are the protective film.
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Thanks, more comfy than chicken-wing posture too. The plan is Speed Week, but I've got a lot to do. That's your plan with Don, right? Shakedown meet with modest engine?
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Thanks, more comfy than chicken-wing posture too. The plan is Speed Week, but I've got a lot to do. That's your plan with Don, right? Shakedown meet with modest engine?
Excellent, see you at Speedweek if all is settled down at Casa Sabatinelli.
Yup, you have our Plan exactly right.
1. see if it goes straight
2. learn to consistently pull the HS parachute and not the engine bay fire bottle
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Dean:
If you've told us about your new bike project I missed it. So - how 'bout telling us about your new bike project? Thanks.
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Great up date. I enjoyed this build the first time. It will be great to see the lakester run in its new configuration.
Thanks for the tweak diary
BR
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Very nice new chapter guys!
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Motec on an NA bike?
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Sorry to divert the thread, I PMd Jon and Ransom about the bike.
Karl / Don, are the wheels, chassis lengthening and windscreen the major changes? Anything else planned before its debut? Will it be painted green? :)
Dean
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Sorry to divert the thread, I PMd Jon and Ransom about the bike.
Karl / Don, are the wheels, chassis lengthening and windscreen the major changes? Anything else planned before its debut? Will it be painted green? :)
Dean
Dean there are a few other things besides chassis +22", custom zero scrub wheels, and new design canopy/windshield...
- new latching, hinges & locking supports for canopy
- skin replaced as necessary to improve engine access
- new air scoop
- new rear axle, moved 13.5" rear, added adjustable height & F-B (help weight distribution)
- lateral hand protection bars added
- leg belt added
- new customized seat and all seatbelt anchors replaced, seat belts upgraded
- cabin cladding to protect driver from chassis tubes
- steering wheel & linkage replaced
- transmission ratcheting shiftgate added
- throttle and brake pedals replaced
- exhaust headers replaced
- waterpump, replaced electric with mechanical, de-pressure watertank
- electrical switch/fuse block replaced
- add complete Racepak digital dash & data recording system, F&B facing vid cameras
- front hubs replaced with new units
- new rear brake calipers and pads, master cylinder relocated
- firewall replaced, added 2 x 2" Lexan viewing ports
- 2 lateral helmet restraint plates, custom padded, added
- cabin tubes padded around helmet.
- helmet forced air system installed
- will add lead ballast to nose to get 55/45% or more F/B weight distribution
- powder coat chassis white
- paint car dark metallic blue with white belly
Don is being a very busy boy!
Karl
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just a postscipt here.
Some may notice that no hp issues are addressed.
we have a 2014 plan as follows:
2014 Objectives:
1. Build/modify a good looking Lakester with no compromises on safety, handling, reliability, driver ergonomics, data monitoring.
2. Don & Karl get solid experience in each personally driving a 200mph parachute car at Bonneville.
3. TFA Racing Team develop & implement robust operational procedures & checklists
4. Develop accurate predictions of #5448's "mph vs hp" potential (chassis dyno + actual Bonneville speeds + wind tunnel)
5. D&K make informed decision for 2015 season:
- make our TFA Racing Lakester faster, or
- make our TFA Racing Lakester slower, go for record
- make "minor" improvements and run it for "cheap" fun
- sell the car and take up fishing
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just a postscipt here.
Some may notice that no hp issues are addressed.
we have a 2014 plan as follows:
2014 Objectives:
1. Build/modify a good looking Lakester with no compromises on safety, handling, reliability, driver ergonomics, data monitoring.
2. Don & Karl get solid experience in each personally driving a 200mph parachute car at Bonneville.
3. TFA Racing Team develop & implement robust operational procedures & checklists
4. Develop accurate predictions of #5448's "mph vs hp" potential (chassis dyno + actual Bonneville speeds + wind tunnel)
5. D&K make informed decision for 2015 season:
- make our TFA Racing Lakester faster, or
- make our TFA Racing Lakester slower, go for record
- make "minor" improvements and run it for "cheap" fun
- sell the car and take up fishing
Sounds like a great plan and a more realistic one than I often read :-),
Sum
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One your "to do" list you have replacing the electrical water pump with mechanical and "depressurize water tank" What does this mean, you are not running any pressure in your water system??
Rex
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I knew there was lots more :) Thanks for the update Karl, I look forward to seeing the car progress over the next few years. Also, fish is sold in stores.
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One your "to do" list you have replacing the electrical water pump with mechanical and "depressurize water tank" What does this mean, you are not running any pressure in your water system??
Rex
The workmanship of the car was excellent as we bought it, but both Don & I were concerned about the integrity of the large-ish home-built water tank when pressurized.
So we plan to put a restriction on the filling where the water leaves the motor, pressurizing water in the motor
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I knew there was lots more :) Thanks for the update Karl, I look forward to seeing the car progress over the next few years. Also, fish is sold in stores.
bahahahahahahahahahahahaha That's true, Dean.
Besides, the 10 years or so i spent obsessing over fresh water game fish left me with a big problem almost every month.
Many of the times i did my monthly accounts, there was money left over.
It worried me, what to do with extra money?
Then i discovered LSR
worries gone.
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Fresh water game fish???
Which ones?. :cheers:
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Fresh water game fish???
Which ones?. :cheers:
Payara (Colombia & Venezuela)
(this is not me, i just grabbed a pic from google)
(http://www.fishquest.com/images/Web_Trip_UraimaFallsLodge_Index.jpg)
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Powder coating of the chassis is done, now we can start bolting it together
(we are aware of the pros & cons of powder coating, but pc suited our plan)
still very warm from baking
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_2199_zps4e77dcf4.jpg)
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_2202_zpsc0beb6cc.jpg)
(http://i206.photobucket.com/albums/bb194/guntekd/IMG_2227_zpsd3c5336d.jpg)
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If you don't mind my asking, how much does it cost to get a tube chassis powder coated?
Regards, Neil Tucson, AZ
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Fresh water game fish???
Which ones?. :cheers:
Payara (Colombia & Venezuela)
(this is not me, i just grabbed a pic from google)
(http://www.fishquest.com/images/Web_Trip_UraimaFallsLodge_Index.jpg)
Nice Fish.
I thought maybe Bass.
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If you don't mind my asking, how much does it cost to get a tube chassis powder coated?
Regards, Neil Tucson, AZ
Neil,
We were prepared to spend up to about $2500 to get the chassis completely blasted & powdercoated.
Lucky for us the deal offered to us by David of Texas Custom Coaters was way less than that because our job piqued his interest; he said it was a fun diversion from his customary industrial stuff.
Even though we got a great deal, he didn't skimp on the work. We told him we were concerned about an orange peel surface on the steel sheeting over the cabin because it will be part of the car's "skin". He said don't worry...
After using a fine grit blasting sand he baked the car in the oven to drive off all water, then (presumably) let it cool a bit and sprayed the paint, then baked it to set the paint. I think he said 450 degrees for an hour or so. The finish came out beautifully.
My only experience with price & quality of powder coating has been misc motorcycle parts, but it sure looks great to me.
Karl
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Karl, he did a great job.
The inside even got full coverage.
I'm happy for you.
It looks just great. :cheers:
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Karl, he did a great job.
The inside even got full coverage.
I'm happy for you.
It looks just great. :cheers:
tauruck,
Thanks!
Like i said, i have very little experience with with to judge the job, but the TCC owner i dealt with, David, said he was very proud of how it came out. That made me feel good.
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I agree with Mike- he did a great job!
Regards, Neil Tucson, AZ
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Good "wrap" of powder on all the round tubes is hard. L:ooks good from here.
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The car is looking great. We were hoping to sell it to someone who would do it justice. Looks like we got the right guys. The canopy is awesome!
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The car is looking great. We were hoping to sell it to someone who would do it justice. Looks like we got the right guys. The canopy is awesome!
hey Chuck, thanks for the words! :cheers:
Don is a really good fab guy and it is coming out great.
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Word on the street is you had an awesome time at WOS ! Tell us all about it! I hear tell the car performed well.
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Word on the street is you had an awesome time at WOS ! Tell us all about it! I hear tell the car performed well.
hey Chuck!
TFA Racing did indeed have an awesome time at WOS!
Car ran great, nothing broke, made 8 passes, we had a ball.
Don & I & TFA Team members Brother Bob & Bill & Jake came together as a Team, we all learned a lot.
(As a "special student" I got an extra, hands-on, last-pass lesson in throttle control at the 5 which i will not forget)
As soon as i gather some pix, I'll post 'em.
Thanks to you Chuck for building/providing us with such an excellent starting point.
Thanks to Tom Burkland & Rex Svoboda & Stainless Steele for patiently and enthusiastically answering a myriad of questions.
(I think I determined that Tom probably sleeps from 1-4am, maybe less...)
Thanks to my partner Don Davila for inspired & tireless fabrication.
Thanks to USFRA for again hosting such a great meet! WOS feels more like a family gathering than a formal event.
:cheers: :cheers: :cheers: :cheers: :cheers:
TFA Racing WILL assuredly be back in 2015!!
Karl
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ahhh does that mean you had never driven an OLDs Toranado down hill too fast, on a curvy gravel road :? or over an icy bridge?????????
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Karl, REALLY GREAT to meet and talk with you at WoS. I, like you, enjoyed the meet and WILL be back in 2015!
I thought I hade more pics of the TFA lakester but this is the only one I could find.
(https://lh6.googleusercontent.com/-_EixWzJcwjc/VAvMmB4NpOI/AAAAAAAAB6E/RZZhcoMEyK4/w800-h600-no/IMG_0060.JPG)
Gregg Adams
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ahhh does that mean you had never driven an OLDs Toranado down hill too fast, on a curvy gravel road :? or over an icy bridge?????????
bahahahahahahahahahahaha, nope never drove a Toranado over an icy bridge, but I owned a 71 Cadillac ElDorado cov at one point. Does that count?
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Karl, REALLY GREAT to meet and talk with you at WoS. I, like you, enjoyed the meet and WILL be back in 2015!
I thought I hade more pics of the TFA lakester but this is the only one I could find.
(https://lh6.googleusercontent.com/-_EixWzJcwjc/VAvMmB4NpOI/AAAAAAAAB6E/RZZhcoMEyK4/w800-h600-no/IMG_0060.JPG)
Gregg Adams
gregg,
thx much for stopping & chatting and the pic :cheers:
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I have posted 10 pix in "World of Speed 2014 Picture Post" thread (it took me about as much time to make that post as Don spent fabricating the canopy :-D http://www.landracing.com/forum/index.php/topic,14391.msg261676.html#msg261676 (http://www.landracing.com/forum/index.php/topic,14391.msg261676.html#msg261676)
Karl
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lol A '71 El DoDo does count--
-I almost went over the side of a mountain with a '75 Toro learning that the FWD that pulled me up and around the curves when I was hard on it going up ---almost killed me as I came down---it wanted to go straight ahead when I got out of the throttle it plowed straight ahead----I had to get back in it; to get around the curve and then put it into neutral to get slowed down and stopped so that I could clean the car out and let the adrenaline wear off!!!!!!!!
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Glad to see shots of that car on the salt. I watched Chaz and crew for years and I am sure it is a bittersweet happiness for them as well. :cheers:
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Glad to see shots of that car on the salt. I watched Chaz and crew for years and I am sure it is a bittersweet happiness for them as well. :cheers:
Its not really all that bittersweet- Just sweet. We took that car as far as we could afford to. Karl and Don were a perfect fit. They are experienced and VERY capable. They made it happen! Our hats are off to them. What an accomplishment! Its hard to go fast on a budget nowdays. but the cars' success proved to us that front wheel drive, a crate engine and mostly stock and home made parts can be pretty successful. In our calculations we figured the car would top out at 213 MPH. Karl's run was right there. We had a ball building what we did and have no regrets at all!!! We'd engineer and start another one tomorrow if someone would sign the checks for it!
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Chaz, I know it is about the building for you. Congrats on seeing your ideas proven!
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Glad to see shots of that car on the salt. I watched Chaz and crew for years and I am sure it is a bittersweet happiness for them as well. :cheers:
... In our calculations we figured the car would top out at 213 MPH...
Chaz,
I'm thinking your 213mph calculation will turn out to be very close; i'm guessing 215-ish when (if) Don & I learn how to drive better. Maybe even more :-D
On my last pass, 1st time on the long course, the last mile & exit speeds were 208/209, but i'm guessing there is more to be had.
1 - My run up in 1st & 2nd showed very sloppy throttle control. I'm thinking we need to push the traction envelope a lil harder, and also consistently run the shift point as high as is healthy for the motor.
2 - In 3rd gear, i tried to be WOT from the 2-3 shift thru parachute deployment, but the Throttle Position log shows many small dips, maybe due to track bumpiness? Gotta concentrate better,
3 - Neither Don nor I are completely comfortable with how the car hunts around the track a bit, so we are both somewhat "throttle-tentative" at this point, not agressive enough.
4 - other stuff we don't know about
We are told that the car has a great Cp/Cg relationship and that it will mostly correct itself like an arrow in flight, but it takes some getting used to. I'm kind of a chicken and our motorcycle background makes us alarmed when the handling is anything but rock solid.
Basically we are complete noobs and we would love to hear any tips on how we should drive our car better. In fact, after the event, Don & I changed our 2015 strategy.
Previously we were talking about going to higher hp/more efficient engine /trans. But now, after actually driving the car, it is likely we will do some checking & tweaking, but will stay at our current basic config and concentrate on learning to consistently drive the livin' pistol out of it.
Sorry to get carried away... :cheers:
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Just about everyone comes back from a run saying that their car feels like its driving on ice and that it dances a bit. We figured that it would take 3 years to sort out all the small issues, and then we'd try for a NASCAR engine that has about 850 hp and can turn 10,000 rpms with reliability. That'd get us near the record we figured. You can probably tell by now that we are not engine builders.( We refer to them as "spacers". They fill up the space between the driver and the transmission) We keep looking for something that comes in a box...
I really think that you guys had about as successful a first outing as can be had. CONGRATS!
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Just a thought regarding your front alignment. Are you running any toe in or toe out. Typically toe out can cause a certain amount of hunting also lots of caster is always good to go straight. I was helping Steve Nelson with his V4 Fuel Lakester at the meet and this car has a rear engine and drive, it is based upon a Albatross drop tank that has been lengthen, no rear vertical stabilizer, at best the CG and CP are probably at about the same place. We ran a best of 202.6 got the record over 200, (Red Hat for Steve!) and it runs absolutely straight, no wondering, Steve says he could easily drive it with one hand. He runs about 1/16 to 1/8 inch toe in. Admittedly toe in (or out) causes tire scrub which takes power but it can add stability.
Rex
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Just a thought regarding your front alignment. Are you running any toe in or toe out. Typically toe out can cause a certain amount of hunting also lots of caster is always good to go straight. I was helping Steve Nelson with his V4 Fuel Lakester at the meet and this car has a rear engine and drive, it is based upon a Albatross drop tank that has been lengthen, no rear vertical stabilizer, at best the CG and CP are probably at about the same place. We ran a best of 202.6 got the record over 200, (Red Hat for Steve!) and it runs absolutely straight, no wondering, Steve says he could easily drive it with one hand. He runs about 1/16 to 1/8 inch toe in. Admittedly toe in (or out) causes tire scrub which takes power but it can add stability.
Rex
Rex,
Thanks much for the thoughts. Every suggestion is very much appreciated!
Our crew checked toe in at the track, and IIRC found it was a tiny bit "toe in", so they set toe-in to 1/8" as best as they could with tools available. We will put the car on an alignment machine and check/adjust.
Also we will re-re-check scrub.
Karl
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Karl, you may want to check the toe in in the rear. If there's any toe out the car will definitely be squirrelly. I'm not sure what you have for a rear axle but toe can easily be set on a solid axle by bending, usually using heating and cooling. The other thing to make sure is that the toe is equal on both sides and not all on one side. The car has to run straight.
Pete
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Karl, you may want to check the toe in in the rear. If there's any toe out the car will definitely be squirrelly. I'm not sure what you have for a rear axle but toe can easily be set on a solid axle by bending, usually using heating and cooling. The other thing to make sure is that the toe is equal on both sides and not all on one side. The car has to run straight.
Pete
Pete, thanks a million for the tip!
Rear toe was not on our list, now it is.
Karl
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Also , although you've probably done this, check the rear axle for being perfectly perpendicular to the car's centerline. Just a thought.
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Also , although you've probably done this, check the rear axle for being perfectly perpendicular to the car's centerline. Just a thought.
Chuck,
Thanks for the thought. I particularly appreciate you suggesting something that "you've probably done this".
People tend NOT to suggest things that are basic, but what is basic to long-timers may be a revelation to noobs (like me).
I'm lucky to have a partner like Don, who has long experience with automotive issues, but he's also a salt noob.
Once i get our preliminary list of "set up stuff to check & driving tips related to handling", I may start a thread in the Technical Discussion section on those issues and get a wider audience.
karl
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Karl
If I recall your driveline doesn't have an over-running clutch . The advantage of the pull of the front wheels becomes a negative during deceleration when the car is pushing the front tires . A couple of brands of what drag boats call whirlaways or prop releases can be adapted for FrWD cars . These are available from Casale and a company in Texas who's name I've forgotten . Sprag clutches don't seem to work well in this application .
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John,
You are exactly right, our car does not have an over-running clutch. We have kicked around various ways of getting the car to free wheel during decel, but it wasn't a priority. I suspect I wouldn't have gone into that slide at the 5 if we had one, but i sure as heck will be much more careful coming off WOT next time.
Thanks for the info
Karl
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I'm thinking that when (probably not always if) the crankshaft stops going around suddenly for a variety of reasons, you may not have time to disengage it before it sends the car somewheres.
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John and Stan are correct, you should really consider the upgrade. BTW, I like the car and I am sure you will have many years running it. Be safe and go fast. :cheers:
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Karl
Beaverfab is the one from Texas I couldn't think of . JJ the owner used to post here and I'm sure would be helpful . Beaverfab and Casale both come with a neutral position handle that is unneeded for our use .
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Karl
Beaverfab is the one from Texas I couldn't think of . JJ the owner used to post here and I'm sure would be helpful . Beaverfab and Casale both come with a neutral position handle that is unneeded for our use .
John, thanks much!
Karl
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Issue:
At the recent WOS, my Partner & I made a total of 8 passes and in all of them we both experienced the car hunting at speed to the point we momentarily got out of the throttle or were throttle-tentative.
Experts say that some degree of this type handling comes with the territory with FWD car on salt. On my last pass I was WOT for all of 3rd gear except once and the car does indeed "fix itself". Maybe we are not driving it right.
Don & I are ex-motorcycle guys so maybe we are just being over sensitive, but in any event we'd like to minimze the jinking/hunting because it spooks me somewhat. Besides... My MC experience taught me that getting out of the throttle at ANY point on the course costs mph (except as dictated by traction management)
Below is a hit list of issues to address; we'd like your comments.
#5448 handling issue - set up stuff to check/adjust:
1. Would adding 300# F ballast help stability? (gives 55/45%) Pros & cons
2. Re-determine our Cg-Cp relationship, basic vehicle info
3. Re-check L-R tire psi are equal; is F-R psi a factor?
4. Further minimize play in steering linkage, improve mounting of associated universal joints
5. Confirm scrub radius is close to zero, find a way to measure it more accurately
6. Other?
7. Put car on automotive alignment system:
- measure castor; lots of caster is always good to go straight (not adjustable)
- measure front toe in; set to ?1/8?", is it better to err on the side of more or less toe in?
- check the rear axle for being perfectly perpendicular to the car's centerline
- check the toe in in the rear, assure it is equal on both sides and not all on one side
- other?
I was torn between posting this here in TFA's thread or posting a new topic in the Technical Discussion section.
It went here because I am such a noob with my A, B, C's-type questions and the issue is specific to TFA #5448.
Our Mentors are VERY well versed in this stuff & eager to talk about it, and my Partner Don has strong automotive & aircraft experience so why even put this question here?
I am just learning and am looking for as wide exposure/comments as possible. Sometimes two people can say the same thing differently, one way rings my bell, one way goes over my noob head. Thanks for your help.
Karl
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Once again I am speaking out about something I know nothing about. But on your list i didn't see check front tires for roll out. On a rear drive car i found pressure equalization to be not important compared to diameter. Maybe it is important, I just didn't notice it. But diameter is for sure important, I think.
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.....
4. Further minimize play in steering linkage, improve mounting of associated universal joints
8. ...measure front toe in; set to ?1/8?", is it better to err on the side of more or less toe in?..
Definitely try and minimize any play and that also ties into 'toe in'. It was always my understanding that the primary reason for 'toe in' is that steering and the other frontend components will always have some play (give). Toe In helps to getting the wheels/tires going straight down the road once the car is underway and the slack/play/give goes out of all of the steering and other frontend components. How much? Probably depends on how much play there is in ever thing and all vehicles don't have the same combination of frontend parts.. I'd rather have a little to much toe so would start on the high side of what has been suggested. With that said I think Hooley has the Stude setup with some 'Toe out' (Hooley ??) and the car steers like it is on rails.
.....
5. Confirm scrub radius is close to zero, find a way to measure it more accurately..
7. ...measure castor; lots of caster is always good to go straight (not adjustable)
Don't forget that castor effects the scrub radius along with kingpin inclination and tire height. The way that I've always understood it (someone correct me if wrong) is that it is the projected point on the ground that the tire pivots on. More castor will move that point further forward resulting in the point being further from the cars center line.
I personally believe that unknowingly people have tried to fix, or over come, what was actually a 'scrub radius' problem (car hunting, darting around) by putting a lot of castor in the car. If they would get the 'scrub radius' right there would be no need for all of the castor. Just my opinion,
Sounds like you have a well though out plan and sure you will end up with a car that is easier and fun to drive,
Sum
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I agree with Rich on rollout. More important than pressure. Set the largest tire to the pressure you want to run, than add more to the smaller one. We try for 1/2 inch difference. Less if we can get it. Sometimes we can be right on.
And always re check air at the starting line. The right side always gains from sunshine exposure.
Frank
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2. Re-determine our Cg-Cp relationship, basic vehicle info
Is your base data measured using your heaviest driver in the seat (and fluids in tanks) or empty/dry?
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Can you slow the steering down?
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Maybe rethink that steering reverser a little. Those gears are over kill anyway.
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CASTOR the helps nothing-- it hurts --weight jacks the car when you "Steer"----my suggestion--read and study front wheel drive drag cars ---I think Sum is right about the toe in---FWD drag cars start with toe out so that it pulls into alignment under power---talk to Bob Johnson your fellow class member!
My opinion---You are already on to the biggest thing---DRIVE to the Chute---I would THEN ease off the throttle to ZERO thrust ---then shift into neutral for roll out---
your advantage going down the track under power will work against you when you are try to slow down your breaking and steering are nearly all on the same tires. YMMV
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This has been my experience on the salt. The first time I drove Bonner Denton FWD AA/BFMS over 2000+ HP I went about 190 MPH @ the @ 2 1/4 the car was hunting all over could not understand how he ever drove this thing 300+
I cut the run short. I ask Bonner what the toe was and he said it was set 1/8 in. So trying to get in my head what all that HP was trying to do to them front tires I asked about setting the toe an 1/8 out he told me well your the one driving. The next pass the car drove so much better I felt like I was driving the car instead of it trying to drive me oh one that pass 2 1/4 speed was 240+MPH the car had never seen a speed that fast that early in the run. Now I know all car are different but front wheel drive the tires are trying to pull together just the opposite from rear wheel drive.
Remember this is what worked for me and something for you to think about.
Donnie Stringfellow
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....FWD drag cars start with toe out so that it pulls into alignment under power---talk to Bob Johnson your fellow class member! ... Sparky
....So trying to get in my head what all that HP was trying to do to them front tires I asked about setting the toe an 1/8 out he told me well your the one driving. ..Donnie Stringfellow
I think Sparky and Donnie are onto it and I'd reversed my comments about amount of 'toe-in' to trying 'toe-out' first.
In rear-wheel drive the front tires/wheels are being pushed so as all of the play gets pushed out at speed the toe-in goes to probably close to neutral.
They are right that with the front wheels/tires pulling, starting with toe-out when the play in the front-end is pulled out the tires/wheels will become more neutral. No matter how hard one tries there is going to be some play in the front end that will go one way or the other.
Possibly setup toe-in and toe-out and have marks so you can go to either fairly quickly on the salt.
Hopefully you re-post all of this next summer after running with what you finally did and the results.
Sum
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I received a message from Tom Burkland regarding the alignment options on the TFA lakester and Tom mentioned that on a FWD car large amounts of caster maybe is not a good idea. Caster increases the trail of the suspension in side view, which means the tire, which is pushing forward, has a longer lever arm to try to disrupt the direction that it is pointed when deflected by an outside force, like a bump or a driver correction. As the caster is decreased the lever arm is shortened and the steering should become more stable but this also means that the steering mechanism should be very stiff i.e. minimum deflection related to applied load, so such things as the steering links from the steering box to the wheels should be large diameter and the steering arms should be stiff and the rod ends should probably be larger and probably should be in double shear on both ends and the mounting of the steering box itself should be very stiff.
Imagine a caster style wheel, like the kind on one end of your tool box, it is allowed to pivot around a vertical axis which allows you to "steer" your box around the shop, this works pretty well because the caster wheel has lots of "trail" (the offset between the wheel axle and the vertical "steering" axis) and the force that the wheel applies to the vertical axis is behind the axis and is in the opposite direction of movement. So now imagine if you could now apply a drive torque to the wheel so it is trying to push forward on vertical axis, as soon as there is any misalignment of the wheel (now driving forward) with the centerline of vertical axis, the wheel will want to drive around the vertical axis, which means it is no longer pointed forward. This argument probably could mean that using zero or possible some negative caster may be the most stable under power . This configuration could possibly have a stability problem at trailing or no throttle conditions because of the lack of positive caster. I think I would really consider a good steering dampener.
Regarding toe in or out for driven wheels it is probably very dependent on the scrub radius. If the scrub radius is positive (a line through the steering axis falls outside the center line of the tire patch) as drive force is applied the wheel wants to turn outward increasing toe out which would indicate that a static toe in alignment would be desirable. If the scrub radius was exactly on the center of the tire patch there should be no increase or decrease of toe due to the drive force, and obviously if the scrub radius is negative the drive force will cause a torque about the steering axis to increase toe in. All this being said I believe that any toe out on a driving wheel (front wheel drive or rear wheel drive) is not desirable and can cause direction instability, so my recommendation is to always align the wheels with toe in. The amount would be very dependent on the stiffness of the steering system to reduce deflection due to drive wheel torque inputs around the steering axis.
Rex
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Rex, good and wise words. :cheers:
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I'm not convinced that caster causes a problem with front wheel drive . If the contact patch is directly inline with the kingpin axis (zero scrub) how does the distance between them change things ? When the wheels are turned adding caster makes the tires lean more but steering input during a run is very small . Ken Walkey said his FrWD streamliner handled well with 26* of caster .
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operative word here is---ZERO scrub radius
I would try to figure out my tire growth and either go with slightly negative scrub radius to allow for tire growth or build center point king pin frt axles
do not discount torque deflection---study what the frt wheel drag guys have gone through in the last 20 years there is a reason nearly all of the high HP fr wheel drive production cars have torsen-gleason
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Been a lot of yrs since i did wheel alignments but
hunting to me has usually been a toe in/toe out issue , excessive of either ,in this case i agree with Sparky , some tow out to compensate for "pulling the car along between the wheels "
the other influence this yr is the salt condition, it was soft and possibly getting differing traction conditions from one side to the other as you ran , i want to say it will feel light on one side or the other but its not quite the right description and will feel less regular than hunting from toe in
but all influences interact
Karl our busa was "hunting " too about 2-4 times a second ...., that i can do without
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Good info Rex, but I do have a question about the following....
...and obviously if the scrub radius is negative the drive force will cause a torque about the steering axis to increase toe in. ....Rex
Other than cars running A-arms and such which I don't know much about most cars with front axles like you find on roadsters, lakesters and streamliners (maybe) and maybe the case for this front wheel drive lakester have negative scrub (some a lot). If that is the case and according to your comment above...
if the scrub radius is negative the drive force will cause a torque about the steering axis to increase toe in.
... the drive force will increase toe then wouldn't you want some 'toe-out' to begin with as the force would then help to straighten the wheels/tires out. If you started with 'toe-in' then it would just become more. Possibly I'm not interpreting what you are saying right??
Sum
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Sum,
My thoughts are are when you step of the gas with a FWD car and if you happen to have front wheel brakes, which would be appropriate on a FWD car as most of the weight is (or should be) on the front wheels and toe out under braking is unstable. Now looking at the pics of the TFA car they do not appear to have front brakes so this may be a moot point with them. On a car that wants (needs) straight line stability I don't think I would ever recommend toe out. On road racing cars slight toe out can help turn in but they are usually not slowing from 200+mph.
John Burk, I would love to see the details on the Ken Walkey FWD streamliner. Specifically the amount of scrub radius and the configuration of the steering system. 26 degrees does sound like a ton but maybe the steering configuration was such that the turning loads that could be generated by caster were restrained and dampened by the steering system. FWD is something that we don't see often and some one that has an operational system would be great to talk to. BTW John how is your FWD streamliner coming????
Rex
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Charles Nearburg bought Ken Walkey's streamliner besides the Harold Nafziger's streamliner he races .
Health has slowed things on my FrWD streamliner but it should be at the salt next year . Thanks for asking Rex .
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Once again I am speaking out about something I know nothing about. But on your list i didn't see check front tires for roll out. On a rear drive car i found pressure equalization to be not important compared to diameter. Maybe it is important, I just didn't notice it. But diameter is for sure important, I think.
Rich, excellent point and one that i had given no thought to wrt handling, THANKS
we are careful with rollout as I zero in on the calibration of the front wheel mph log (hall effect)
we were specifically advised to match our front tire diameters, so i think we are OK, but thanks again.
karl
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I agree with Rich on rollout. More important than pressure. Set the largest tire to the pressure you want to run, than add more to the smaller one. We try for 1/2 inch difference. Less if we can get it. Sometimes we can be right on.
And always re check air at the starting line. The right side always gains from sunshine exposure.
Frank
Frank,
We set F tires pressure to 90psi in Houston (sea level+/-) before leaving: both L&R circum were 91.25"
At WOS 9/5 L = 91.75 @ 74psi, R = 91.5 @ 73psi (tires free standing)
9/7 L = ? 76psi, R = ? 77psi (tires on salt), didn't re-measure cirum bc psi was so close
I thought the decrease in psi & increase in circum wrt sea level was an altitude effect, but i didn't cogitate on it very much.
Interesting thought on sunshine exposure, this never occurred to me. Do you have any measurements which demonstrate this effect? I don't doubt it, just wondering how much it affects the tire.
Karl
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2. Re-determine our Cg-Cp relationship, basic vehicle info
Is your base data measured using your heaviest driver in the seat (and fluids in tanks) or empty/dry?
After stretching the car, CP is aft of CG by 42",
We did scale the car with fluids and driver, but that 42" is probably +/- 6".
Our todo list includes doing the calculation more carefully.
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I felt like I was driving the car instead of it trying to drive me
Donnie Stringfellow
My experience was like that, not severe, but I was wondering what the car would do next...
However, my total of 4 car passes ever = pure n00b, this is why all ya'lls input is so valuable
Karl
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Maybe rethink that steering reverser a little. Those gears are over kill anyway.
the steering reverser box is definitely uner scrutiny. The gear lash is very small but it could be less.
karl
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...Hopefully you re-post all of this next summer after running with what you finally did and the results.
Sum
Sumner, SPARKY, Donnie,
110% yes, we'll re-post next summer, I love this stuff!
Trying a lil toe out was suggested to us but we just ran out of time.
One of my WOS personal objectives was experiencing 5 miles with throttle mashed, see if it was fun, see if i wanted to continue the Project.
It surely was, and I surely do!
I got a lil more excitement than I expected but that slide at the 5 was totally my fault, excellent lesson, hopefully won't make that mistake again.
Karl
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Karl,
It is always good to ask questions. This thread has a lot of good information. The way Jim Kirk and I work out issue's
we take all the info and discuss it until we agree. Sometime we have to have our phones plugged in because a cell phone battery won't last that long :-P.
Now that you have a few pass in the car you can make a change and know what it did. Don't make too many changes at one time. Remember there in no rule that say's you have to go to the 5 mile.
Sounds like you are having fun.
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If the scrub radius is positive (a line through the steering axis falls outside the center line of the tire patch)...Rex
…uh-oh i've been calling that condition negative scrub… :oops:
But in any event, we had the wheels made so that the tire center was .040" inboard of the steering projection. We figured that we could then shim the wheel outwards wrt the hub to get scrub to exactly zero.
However, I find it difficult to measure scrub that precisely. Does anyone have a clever way of doing this?
Rex: your post is great! I simply have no experience in this kind of thing and can use all the schooling i can get.
Karl
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Maybe rethink that steering reverser a little. Those gears are over kill anyway.
the steering reverser box is definitely uner scrutiny. The gear lash is very small but it could be less.
karl
When I made mine, I had the gears quite snug and then lapped them together for a very nice back lash. I didn't use such killer gears as I thought anything larger than the pinion gear was over kill. And i had access to lots of CF6 sump pump gears that had been replaced.
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Been a lot of yrs since i did wheel alignments but
hunting to me has usually been a toe in/toe out issue , excessive of either ,in this case i agree with Sparky , some tow out to compensate for "pulling the car along between the wheels "
the other influence this yr is the salt condition, it was soft and possibly getting differing traction conditions from one side to the other as you ran , i want to say it will feel light on one side or the other but its not quite the right description and will feel less regular than hunting from toe in
but all influences interact
Karl our busa was "hunting " too about 2-4 times a second ...., that i can do without
maj/Greg (same as OzBooster, yes?)
The possibility of differing L-R traction causing hunting didn't occur to me at WOS but afterwards the possibility was suggested.
One would think if the hunting was due to L-R accel/traction differences, hunting would stop during decel
So i just looked at my 5 mi log.
Last pass, 3rd gear / 205mph I got spooked by the hunting and briefly went to about 50% throttle, 199mph.
In my mind i think the hunting must have stopped bc I got back on the gas hard.
But the logs show 1-2.5 degree heading changes even during that brief decel.
I don't understand what's going on, but I LOVE this stuff.
And, i love the Racepak logging system. I am a dumb-azero at set up and use, but with the help of my vendor (Greg Kelly), and help at WOS (Donny Cummins), i am inching up the learning curve...
I feel your pain about dealing with a twitchy Busa on the salt, you KNOW I do :-D
Karl
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Off topic, but I was looking at this picture of a car that was fast and handled well in it's day. And looked at the kingpin/tire center relationship. As I have mentioned, I know nothing about suspension/steering. So can someone tell me why this worked once when we all know it won't work now.
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Off topic, but I was looking at this picture of a car that was fast and handled well in it's day. And looked at the kingpin/tire center relationship. As I have mentioned, I know nothing about suspension/steering. So can someone tell me why this worked once when we all know it won't work now.
(http://www.landracing.com/forum/index.php?action=dlattach;topic=13291.0;attach=48271;image)
I guess I'd have to ask what you mean by "worked once"? There are thousands of street rods running around with terrible scrub radius issues but work just fine for the owners. The first time I gained knowledge of the 'scrub radius' deal was in the 90's talking to some guys with a roadster that ran about 160 if I remember right. They had been driving it but said that it 'hunted some'. They minimized the scrub radius and it drove straight. Everyone is probably different in what they will live with or not.
In a different direction in Karl's case I'd do whatever worked to get the car handling where they are comfortable under throttle first and if I had to give up something under braking I'd do that since we use so little braking and when we do the chute should be out and that will cover up some problems right there.
I did a little more googling and found other references to using toe-out for a front wheel drive cars. You can go for extra toe-in or toe-out if you want but the main purpose of either is to end up with the wheels/tires close to straight when underway. Any more, one way or the other, might help straight-line stability or turning in (not important for us).
As I mentioned before I'd put a known amount of tow-in and tow-out at home and be able to reference those points to try either on the salt,
Sum
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I'm not convinced that dead nuts on "0" scrub is necessary but should be very close. That being said, with a straight axle what I did was with the tires on the floor and toe in at "0", to take a .plumb bob from the center of both the front and rear of the tires to the floor and mark on floor and measure height of axle. Then removed wheels and set front axle to right height from previous measurement. Then I turned the grease zerks on the spindle so the flats were parallel, used a lazer level on the zerk flats to give me a point on the floor. Then measured from that point 23/32nds (1/2" lazer offset +7/32=1/2 zerk hex) to get king pin center line. The lazer mark on the floor will be in front of the other marks because of caster. Draw a line through the tire marks to the king pin mark and you will have your scrub taking caster into account. Mine was 1.75" per side negative when I bought it.
There are no doubt more accurate methods but I don't have or want to buy the equipment for a one time use.
YMMV
Ron
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What i meant was it was state of the art, built by a very respected builder of Indy and other race car chassis. A very fast car at the time. Still a lot of fun to drive today, I bet. And nobody seemed to think anything about scrub radius. I wounder about the Novi and Ferguson and Miller FWD cars. They probably had front ends applicable to what is being discussed here
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I'm not convinced that dead nuts on "0" scrub is necessary but should be very close. That being said, with a straight axle what I did was with the tires on the floor and toe in at "0", to take a .plumb bob from the center of both the front and rear of the tires to the floor and mark on floor and measure height of axle. Then removed wheels and set front axle to right height from previous measurement. Then I turned the grease zerks on the spindle so the flats were parallel, used a lazer level on the zerk flats to give me a point on the floor. Then measured from that point 23/32nds (1/2" lazer offset +7/32=1/2 zerk hex) to get king pin center line. The lazer mark on the floor will be in front of the other marks because of caster. Draw a line through the tire marks to the king pin mark and you will have your scrub taking caster into account. Mine was 1.75" per side negative when I bought it.
There are no doubt more accurate methods but I don't have or want to buy the equipment for a one time use.
YMMV
Ron
Ron,
thanks for taking the time to describe yr method. We did something similar when we measured ours to derermine how much offset needed (2 7/16") to build our custom wheels.
I was hoping you'd say: "just go down to harbor freight, the carpentry section and get the $3.99 Crenellated Ramifier (8").
It'll take you 3 minutes, you don't have to remove any parts from the car, and results are good to .0001" :-D
Karl
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GUYS go look up the definition of scrub radius:
By definition
Positive scrub radius---the tire patch is outside the kingpin center line--
Negative " " --- the tire patch is inside the center line
getting very close to ZERO scrub, caster and camber is even more important on a FWD that a rear wheel drive because steering inputs change the thrust portion of the tire patch
My experience with a race car Hunting down the track was limited to my old car---it was horrible---I learned about scrub radius from roadster guys and circle track guys. After lots of research I started getting rid of caster and scrub radius---as well as making my chassis stiffer---wallah a no more hunting down the track
To understand this better I took some old spindles and tack welded them to a piece of pipe. I then put on jack stands and move the tires back and forth with the tire barely off the ground and measured and marked how and where the closest point was.. whacked it off changed the caster and camber----with zero zero --it barely moves but not the case with much of either of caster or camber
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I wonder if you could contact the Hondata guys for some thoughts on speed with FWD. They must know a lot about it.
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I wonder if you could contact the Hondata guys for some thoughts on speed with FWD. They must know a lot about it.
Good idea!
Also, we were pitted next to Rex Svoboda (one of TFA's official Mentors) and he runs the FWD Saab, albeit with a bit more hp (his blower is as big as our motor). Rex didn't seem overly surprised at the handling, but said it can probably be improved by some of the things mentioned.
As pointed out in this thread he suggested systematically test issues/settings. I think that he agreed with confirming toe in at 1/8" as a test (Don talked with him about that item). We came to the event with it set at approx 1/8" but wanted to make sure. We just ran out of time.
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An easy way to see what wheel offset give zero scrub . Put a framing square against where the wheel bolts and clamp it to a couple of wheel studs with the 90* leg down and pointing out paralel to the axel axis . The bottom edge should be at the tire radius . When the hub is steered the point on the horizontal leg that revolves around one point is the zero scrub point . Clamps on the rotors on either side of the caliper only it rotates on the kingpin axis . Don't worry about the vertical leg being at an angle . The effect of caster and tire growth is small compared to the 3" or so of scrub built into the 4wd hubs we use . With 28"tires 10* of caster and 3/4" tire growth only adds .170" of scrub . I'd just check the scrub at bottom center and add .170"
I ordered my wheels with an extra 1/4" of negative offset so the wheels can be spaced in or out to dial in the handling .
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Rich Fox,
Neat pic of the Kurtis roadster, a neat car when it came out and still a neat car. You don't happen to know who owns the one in the picture do you? Notice the tube axle with trailing arm locators and probably a watts link for lateral location and I don't remember but I think that the the top trailing arm is connected to a cross torsion bar, just like his Indy cars. Neat car just like everything that Frank made.
One thing that I think we need to discuss is that positive or negative scrub radius(use whom ever's definition you want) can be a very valuable handling tuning tool, it all depends on what kind of car you happen to be working on. I also think we all agree that minimizing the scrub radius on a front wheel drive Bonneville car is beneficial for handling and from Sparky's previous experience with his first lakester minimizing scrub radius helped that cars handling. Big over the road trucks use close to zero scrub radius because it makes steering loads smaller, which is important when you may have 10,000 lbs on your front axle, but a sprint car may like lots of scrub radius as it can have a big cross weight jacking effect when you back it into a corner. Look at a fast go kart, they may have the wheel spaced out 3-4 inches with a huge scrub radius but they operate in the oversteer mode most of the time and this huge scrub radius helps them jack weight onto the inside tire, so there are places when scrub radius can be helpful.
Rex
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I agree with Rich on rollout. More important than pressure. Set the largest tire to the pressure you want to run, than add more to the smaller one. We try for 1/2 inch difference. Less if we can get it. Sometimes we can be right on.
And always re check air at the starting line. The right side always gains from sunshine exposure.
Frank
Frank,
We set F tires pressure to 90psi in Houston (sea level+/-) before leaving: both L&R circum were 91.25"
At WOS 9/5 L = 91.75 @ 74psi, R = 91.5 @ 73psi (tires free standing)
9/7 L = ? 76psi, R = ? 77psi (tires on salt), didn't re-measure cirum bc psi was so close
I thought the decrease in psi & increase in circum wrt sea level was an altitude effect, but i didn't cogitate on it very much.
Interesting thought on sunshine exposure, this never occurred to me. Do you have any measurements which demonstrate this effect? I don't doubt it, just wondering how much it affects the tire.
Karl
Karl:
2013 speed Week I remember it was consistently 10 psi higher on the right side in staging. I let the air out to what psi I marked on the hubcap in the pit but did not remeasure at the start line.
We have ran as much as 15 psi different across the rear, drive tires to get the stagger out. But that was a few years ago running a set of mismatched used tires.
We run the 18" M/T's. And have found when you buy a new pair right from the source they match up nice and grow with pressure evenly.
I have never put any thought into altitude effects either. I think leaving them at high pressure stretched them. And I leave the air high on them too when stored and transporting. I see no ill effect. Some say to let them down to low pressure for transport and storage.
BTW, this years set was marked 92 as delivered and when mounted and aired to 110 they went to 96. I wonder how big they will be when we get them to WF?
Frank
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I sure hope you guys get it done this meet "old what's his name" has waited long enough to put two runs together
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The Kurtis belongs to Peter Hendrickson. Leader of the Montana Dodge Boys. He just bought it. Appears to be branching out.
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Guys,
Thank you all soooooo much for your input, GREAT discussion. :cheers:
Be assured Don & I will review/use it as we attack the handling issue over the winter. Note that I obsessively copy & paste all comments into one of my many excel spreadsheets, tabbed in a way that I can reliably find the info. Don (and our Mentors) will attest to my addiction to spreadsheets :-D.
An interesting associated comment...
Yesterday I talked to Allied Wheel Component's Greg Mulkey; the guy in LA who made our cool 2 7/16" offset Al wheels. I was giving him a summary about tech inspection of his wheels, other racers comments, how they performed at WOS, etc.
He was particularly interested in my comments on "hunting", said he knew nothing about salt, but that his Baja-type race truck did the same thing on dirt/sand at speed. Greg mentioned that it took him "hours" of racing the truck until he got comfortable with it. Said a light touch on the steering wheel, minimize changes, know it will mostly re-orient itself after it's "hunting expeditions", mostly...
Like you guys, Rex & Tom, he advised us to check all set-up factors & then make single changes at the track, but noted "there may be nothing wrong with your set up, you may simply need to learn to drive it..."
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Sounds like he drives a roadster :?
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Oh, i almost forgot this...
One item on our list hasn't been kicked around and maybe it shouldn't he on that list at all = ballast.
If anyone has thoughts, we'd love to hear them.
As the car sits now with driver & fluids the F/R weight distribution is about 50/50,
The question is: "should we add ballast over the front axle?".
current F/R: 51/49%
add 250# to F: 55.5/44.5%
add 400# to F: 58/42%
associated info:
1. approx 350hp on Dynojet dyno
2. With Tom's help, we found a silver lining in the dark clouds over the recent SW.
Took #5448 to Darko's wind tunnel: Cd = 0.325, F lift = 239#
3. Cp approx 42" aft of Cg
4. 1st & 2nd gears: must carefully modulate throttle to minimize wheel spin.
3rd gear: WOT = very little if any wheel spin
5. car weight 2360# w/suited driver & fluids, no ballast
At this point, I am interested in the impact of ballast on handling/stability.
(I am obsessed with small end acceleration and its impact on big end mph, but that's another discussion)
It wouldn't be horribly difficult to add say 250# ballast (easy for me to say, Don does the fabrication...)
- 250# would counter the 237# lift? So what?
- 250# would add 6"(guessing) to Cp/Cg separation; So what?
Q: would adding F ballast be likely to improve stability?
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Can the ballast be set up such that it can be bolted in relatively easily? That could then become another of the incremental changes that you make. It would also allow you to try various weights and try them with a variety of front end alignment settings.
Pete
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....At this point, I am interested in the impact of ballast on handling/stability.
(I am obsessed with small end acceleration and its impact on big end mph, but that's another discussion)....
I'd put the 400# in the car in an instant. You could always take it out. This could improve your 'small end acceleration' as you aren't using much throttle in 1st and 2nd now because of wheel spin. On the big end where you might be only picking up say 20 mph in the last mile the weight isn't hurting you as almost all the HP is going into overcoming aero drag. How much HP does it take to accelerate 400# of weight 20 mph in one mile? Not much so you aren't giving up much by adding it and if your acceleration gets you to a higher speed by say the 2 1/4 then you have more track at the higher speeds where you need it.
The weight is going to help the CP/CG also which is a good thing. Your car is light now and with more HP down the road you are going to need even more traction. Think what 1st/2nd will be like then. On that thought I'd also explore a different transmission option (one with a closer ratio). I think 1st will become even more useless with more HP. Hooley runs a 1.90 first with 2.47 gears and we can never run more than 50% throttle in first and with the 1.30's second still no 100% throttle and the car weighs over 5000 lbs..
You have one big advantage over most of us and that is any weight you add is all beneficial as it is over the drive tires and also in the right place for improved CP/CG. With a rear-wheel driven car when you add weight at the back for traction you also need to add weight to the front to keep the CP/CG reasonable. The added frontal weight in this case impacts acceleration and doesn't help with traction.
Sum
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Entropy,
The item that I find interesting is that the Cd is .325 which show how the wheels and tires and almost anything else sticking out in the air really spoil what is a very nice shape. My bet is that the body by its self probably has a Cd of .1 or even less. The bain of running a lakester! After you drop the "big" motor in your next project is to do something with that horrible looking front axle to make it better looking to the air. Also doing some stream lining on the rear will help. We added fairing to the rear axle on Steve Nelson's lakester this year and with not to many other additional changes and with the exact same engine that Steve set the record at 196+ two years ago we went 6 mph faster and since I did the axle fairing I will claim that it was all due to the fairing!!!
You guys are destine to have lots of fun!
Rex
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SPARKY
- I am clueless how a roadster handles but have read about the spins they sometimes experience… YIKES!!!! Thinking about my roadster cluelessness emphasizes my need to roam around, go to other pits, yak with many people. For whatever reason, I tend to not roam around; gotta change that.
Peter Jack
- Don & I have kicked around ballast mounting possibilities. Moving the fuel pump & filter would free up space in front of the quick change. Would need to remove the nose to get at it which is doable.
Sumner
- Your post reminds me that I haven't yet "treated" you to my motorcycle-based interminable (largely dismissed) rant on the impact of small end "balls to the wall - show no mercy - take no prisioners" type acceleration :D. But you also make me think again about the possibilty of some of the hunting/jinking being generated as our locked rear end momentarily loses traction on one wheel. This was mentioned earlier in this thread. Would 400# significantly subdue that lopsided traction loss?
Rex
- Fairing the front & rear axles has been on my Partner's list from the beginning of this project. Not only is he an ace-fabricator but also a career pilot so all the aero stuff makes him smile & plan. He mocked up front fairings at Darko and Cd dropped from .325 to .320, but only decreased F lift from .234# to 227#. Don is cogitating...
Notes:
1. At our current config, on WOS pass #8, the car gained 1mph (208.5 to 209.5) over the last 12.3sec leading up to the 5. Is the aero drag close to stalling more mph gains? Maybe the type of aero improvements Rex mentions is our key?
2. Our 2.19 gearing delivered 209.2mph at 5650rpm.
The Patriot motor spec shows max hp is 501 @ at 6100rpm = 226mph estimated max speed.
It seems that we have room to test aero improvements at the current gearing.
I LOVE this stuff!!!
karl
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You mentioned a locked rear (front) end in the above post. Is it a spool or a locker or something else? At this point I might be tempted to follow one of Sparky's favourite suggestions and look at a true track type differential. They tend to have a softer action than some of the other locker types and give you a differential rather than a spool. Just another suggestion to add to the confusion. :roll: :roll: :-D
Pete
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You mentioned a locked rear (front) end in the above post. Is it a spool or a locker or something else? At this point I might be tempted to follow one of Sparky's favourite suggestions and look at a true track type differential. They tend to have a softer action than some of the other locker types and give you a differential rather than a spool. Just another suggestion to add to the confusion. :roll: :roll: :-D
Pete
Being a former m/c guy, I am easily confused about car parts, but i believe our front-rear end is called a "spool" with both wheels turning at the same speed.
What is a "true track type differential" and how much do they cost :-D
Do you think that uneven traction with our spool could cause hunting and that a true track type differential could mitigate it?
I have "call Sparky" on my list but it seems that 2-6am is my only free time these days and few people enjoy being called at that time.
Karl
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read about torsen-gleason diffs
there is a reason why LSR is called the thinking mans sport---there are SOOOOOOOOOOO many trade offs that have to be dealt with:
so much to learn so little time or as the old folks say "old too soon -- smart too late"
or we racers " broke to soon --never fast enough"
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....What is a "true track type differential" and how much do they cost :-D....
I don't think you are going to find a true-track/torsen for your quickchange but also think that at some point you will need to rethink the current quickchange and consider a Winters extremeliner qickchange with a taller pinion ratio or possibly another approach. The frontwheel drive has lots of advantages but also needs to be really thought out well with an overall package approach that addresses gear selection, and overrunning clutch and spool or something like the torsen.
One possible solution, don't know this for sure, would be go to a transmission like what we use in the Stude and what I bought for my lakester, G-Force 101A, where you can do your gear changes with the transmission and even run overdrive gears (also get a 1st and 2nd that is more useable).
Sparky would know if you could setup a 7 1/2 like he uses with 2.14 or 2.28 gears and a torsen in a frontwheel drive axle. That would be a lot less expensive if possible than other options like the few quckchange rears with tall pinion gears. You don't need a clutch with the 101 to change gears so you might be able to replace it with the overrunning clutch from Beaverfab or Casale (check with them).
On the weight it should help overall traction and with the spool if one wheel is spinning the other is also and then the car wants to step out. The torsen/true trac will try and stop the wheel with no traction from spinning and actually send some of the power that was going to that wheel to the one with traction.
I think that I might of run a spreadsheet at one time for you that showed the weight needed over the drive wheels for speeds in the high 200's where hopefully you are going. They might of shown that eventually you might need even more than 400 lbs. more. Let me know if I did or didn't do that and I could do it again or you could do it with the "HP needed for A Lakester or Car to Run a Certain MPH" spreadsheet here (and you said you like to run spreadsheets :-))...
http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html
Sum
Sum
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The torsen/true trac will try and stop the wheel with no traction from spinning and actually send some of the power that was going to that wheel to the one with traction.
....thereby exacerbating the directional “hunting” problem.
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Your lift number may go away if you give the car a little "nose down" attitude. Lowering the front a little should increase front down force by reducing the front ground clearance and therefore increasing the speed of the air flow at that point which will lower the pressure and help eliminate some if not all of the lift you are seeing. I don't know how fast the wind tunnel velocity but remember that lift is a power of 2 function so if your tunnel speed was 100 mph and you had 239 lbs of lift at 200 that would be about 960 lbs of lift. Or is you lift number calculated for 200mph?
Rex
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thereby exacerbating the directional “hunting” problem.
What it does is maximize forward thrust while keeping the wheels turning the same speed! might happen but there must be a reason why most fwd manfactures's use them
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On the weight it should help overall traction and with the spool if one wheel is spinning the other is also and then the car wants to step out. The torsen/true trac will try and stop the wheel with no traction from spinning and actually send some of the power that was going to that wheel to the one with traction.
I wandered into this thread to see what's going on and I'm interested to see that someone else is also going to some trial and tribulation with a newer car. We too (myself and Skip Pipes) have been spending more time trying to get the car situated than making high speed passes. The roadster has all the right things going for it... well constructed, highly adjustable suspension, long wheelbase (for a roadster), good weight and weight placement and yet the car didn't really like to go straight.
I quoted the above because we started with a torsen and have since taken it out. It just simply did not work correctly and we don't really know why. What's strange is that it's worked well for others but was disastrous for us. Since day one, the car would quickly pull to the right at the top of any one gear where the engine is really starting to make a lot of power. We made a short list of possible things that could attribute to the problem and the torsen was the last item as it really wasn't believable that it'd be the problem. We replaced all the Speedway heims on the car with FK heims as some of the Speedway pieces had developed a click to them. We ditched the tape measure alignment job and took the car to an alignment shop. We put the tires that the car was originally built for on and re-adjusted the suspension (had started out with shorter rear tires which made the car too low and required lifting the suspension to get the right ride height). We added a steering stabilizer/damper. We dialed in more caster. We did all the right things that should have made the car happy but the torsen was still acting up. On a test run, everything was going great and the car was going straighter than it ever had and then bam, the torsen wigged out and bad things happened. Basically, what we think was happening was that the torsen was torque biasing for no real reason and sending all the power to left wheel and the car would "rear steer" off to the right.
Well we finally saw the light and took the torsen out. Tested again and viola, no pull to the right at the top of second gear. I used to not be able to rev past 7k in second gear and now I can go 8k+ without the car turning. The only problem now is that the car drives like an open diff car which is to say that the car basically wanders down the course. We ran at El Mirage last weekend and had mixed results. I only managed two 160 passes when the plan was 160, 180 then 200. On the last pass the inertia switch popped. I find that I'm doing more conservative recovery driving and less aggressive WOT fast driving. I've always driven an open diff roadster at El Mirage and I know that rarely does an open diff roadster ride like it's "on rails" or go perfectly straight - it just ain't so. The biggest diff (no pun intended) between Skips roadster and the Stewart Family roadster is the new roadster makes about 5 times more horsepower than our old one so the days of holding it wide open and pointing down course are long gone.
Anyways, long story long, I totally understand and feel you on the getting uncomfortable real fast when a car gets twitchy. It's always better to back out of it and ease back in versus staying in it and trying to "drive through it" because that's when bad things happen. Rule #1 is listen to your gut. If your gut says lift, then lift. As for us, we've got a few other small things to try including adding in a little weight. We're at 3000 lbs wet with a 45/55 front/rear distribution and nearly even from left to right. The other thing working against us was the course wasn't very good - not terrible and not great, just not very good. When the car went from far left of course to the middle and then from the middle to the far right, I kind of just lightly suggested that we think about going to the left some with the steering wheeo. It shouldn't ever be a white knuckle, fist over fist kind of deal - just gently guide the car using small steering inputs with your finger tips. Anything more than that and there's probably something wrong.
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Nate is it possible that something was wrong with the torsen? Sparky ran straight over 300 with one,
Sum
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Nate is it possible that something was wrong with the torsen? Sparky ran straight over 300 with one,
Sum
I think Skip was largely influenced to use the torsen by Sparky's success with his but I think the differences between a long narrow lakester and a no so long and wide roadster erase any amount of "well it worked for them so it should work for us too" thinking. How wide was the tread width on the lakester? I know it's probably no where near as wide as the roadster. If there had been a torque induced rear steering action, would it be as noticeable or noticeable at all on a long wheelbase car with a narrow rear end? Another possible issue is that the axles aren't the same length. The center housing is way offset to the right and the right axle is probably half as long as the left. Perhaps there was axle wind up? Is that even possible? A torsen is a simple device - I don't know how there could have been something "wrong" with it. All I do know is that at about 750 ft-lb of torque, the rear end was doing more steering than the front. And it wasn't the rear end slipping and coming around. It was the rear end making the car turn right like someone was grabbing the steering wheel and yanking it to the right. Not fun to drive. Much better without it.
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It would be interesting to see how a roadster handled with independent or dedion rear suspension handled .
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Ask Rich Fox his has a swing axle.
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You would really have to ask Al Hollaway. He ran it in what is now E/BFR and went 219. Spun a few times but I think that was on shut down. Running with four cylinder engines the car has only gone 142 out the end. Handles fine at those speeds. I believe the Markley-Hoffman 360 roadster has a Corvette type rear end. Maybe they can answer your question. Lately I have been leaning more toward solid mounting.
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....I think Skip was largely influenced to use the torsen by Sparky's success with his but I think the differences between a long narrow lakester and a no so long and wide roadster erase any amount of "well it worked for them so it should work for us too" thinking. How wide was the tread width on the lakester? I know it's probably no where near as wide as the roadster. If there had been a torque induced rear steering action, would it be as noticeable or noticeable at all on a long wheelbase car with a narrow rear end? Another possible issue is that the axles aren't the same length. The center housing is way offset to the right and the right axle is probably half as long as the left. Perhaps there was axle wind up? Is that even possible? A torsen is a simple device - I don't know how there could have been something "wrong" with it. All I do know is that at about 750 ft-lb of torque, the rear end was doing more steering than the front. And it wasn't the rear end slipping and coming around. It was the rear end making the car turn right like someone was grabbing the steering wheel and yanking it to the right. Not fun to drive. Much better without it.
Thanks for the additional info :-).
Sparky is running one in the new car with the widest width he could find, I think Camaro, and he seemed to be fine on his test-n-tune runs in July but I think the fastest before the meet closed was 230 maybe and no where near full power. I'd think his old car, and new, made probably the torque you guys are, but he would have to clarify that. He needs to come up with different mounts for the wide one so think if he runs WF/SW it will be with an older axle that is a little narrower.
With so many differences in the way cars are setup I guess this is another "what works in one car might not work in another",
Sum
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Nate, Thanks for sharing the new ride's "sort out"
If the right wheel was unloading it would transfer more torque to the left and hence more thrust or drive. I run solid and preload the right wheel with a SWAG of how much the pinion is trying to lift the right wheel---hence I start off with more weight on the rr and the lf.. I have about 150# of preload so transfering 75# make them even. I have had suspension and even my low time driving skills I could tell things were changing going down track----
If I were going to try to get a roadster down the track it would be with out suspension or scrub radius and 3-5 degrees of caster
---I am not any kind of engineer but it just makes for less variables in my mind.
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Thanks to everyone for yesterday/last night input!!!!
This thread is really helping me appreciate salt handling factors and driving technique.
But particular thanks to Nathan Stewart for taking the time to review his trials & tribulations; that post 110% rang my bell.
It takes me a while to digest/save this stuff, none of it is taken casually. Specific questions will come and I really appreciate you guys continuing to patiently nudge me up the learing curve.
Once again i am reminded that I need to start wandering around the pits and talk to people at the events like my Partner does. Running a car on the salt is assuredly WAY more complex than the point & shoot impression I had previously.
karl
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Just to address Nathan's long-short axle idea.
We know a NASCAR chassis guy who developed gun drilled axles a few years ago to handle just this situation. His idea was to look at each axle as a torsion bar and remove from the center enough material to even out the spring rate of the axle from side to side. Apparently it works and eliminates that problem.
Probably not a concern with the FD lakester unless the axle shafts are different lengths.
VERY interesting thread!
Frank
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I am pretty sure Torsens or True Track available on several QC system
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After getting a ton of input, here is an updated Handling Issue list
Thanks to everyone!!! :cheers:
#5448 handling issue - technique stuff:
1. minimize amplitude of course corrections, "it WLL come back"
2. Keep a light touch on steering wheel, gentle, smooth course corrections,
3. Both hands on the steering wheel equally, be careful during shifting & parachute deployment
- "SS: parachutes need to be actuated without removing hands from the wheel"
4. Any movement of the eye can be translated into movement of the hands...
5. Feedback: ask an experienced TFA-sized guy make a pass in the car (Tom? Rex? Stainless?)
6. other??
#5448 handling issue - set up stuff:
1. Would adding 300# F ballast help stability? (gives 55/45%) Pros & cons
2. Re-determine our Cg-Cp relationship, document basic vehicle info
3. Re-check L-R tire psi are equal; is F-R psi a factor?
4. Further minimize play in steering linkage,
- look at the steering reverser box, get gears tighter, replace?
- ?replace Heim joints (tie rod ends) w/something better?
- ?replace linkage universal joints w/higher quality?
5. re-measure scrub radius, how close to zero?, find a way to measure it more accurately
6. Other?
7. Put car on automotive alignment system:
- measure castor; lots of caster is always good to go straight (not adjustable)
- measure front toe in; set to ?1/8?", is it better to err on the side of more or less toe in?
- review toe-in vs toe-out
- check the rear axle for being perfectly perpendicular to the car's centerline
- check the toe in in the rear, assure it is equal on both sides and not all on one side
- other?
8. assure both F tires are same diameter, add pressure to the smaller on to equalize (as feasible)
9. assure L&R( F?) tires are at same psi in starting line, sun impact (up to 15psi difference)
10. R tires, assure same circumference, use pressure to equalize as feasible, watch sun effect
11. put laser on car F-B, assure body is straight
12. add steering stabilizer?
13. load/ballast one side of the front more than the other?
14. tq steering from unequal length F axles? (or something like that)
15. check toe-in setting stability under accel stress?
16. re-scale wet car w/suited driver to assure F L&R wheels are equal wt +/-?10?#, also document F/R wt distribution
17. slow steering rate down?
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have you scaled the car with circle track type scales
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have you scaled the car with circle track type scales
SPARKY,
yes indeed we scaled it as received (IIRC, RF = 70# too heavy) and we used a set of scales a second time to set up rear axle adjustment so that F L&R wheels were within 10# or so of each other.
But yr point is very well taken, re-scaling for sure needs to be on the list.
THANKS
karl
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I don't know where or what it is now, but it's almost always a smart thing to slow the steering down from "stock". Imputes at speed can be magnified with "stock" ratios.
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I don't know where or what it is now, but it's almost always a smart thing to slow the steering down from "stock". Imputes at speed can be magnified with "stock" ratios.
Stan,
thanks!
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I was trying to find Chaz original build diary to study the driving frt axle and what brand to determine which side the pinion is on but it must have been taken down!
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. . . also -- putting a smaller steering wheel than "stock" will quicken the steering, too. And in our case, this is often done to aid in getting in and out of the vehicle.
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I was trying to find Chaz original build diary to study the driving frt axle and what brand to determine which side the pinion is on but it must have been taken down!
SPARKY,
This is what is in our spec list for rear end:
Rear End (front wheel drive)
Gear oil: Winters P/N 1730, #293 Supreme Gear Lube, SAE 80W/90 w/moly
Capacity: approx 5 quarts. Fill utill the forward fluid level hole leaks; install fwd plug, then slowly add until the rear fluid level hole leaks
Winters Performance Products, 5270 Quick Change Rear End, serial #C67255 (Apr 27, 2007, Joe Timney - DCW $1638.28)
10" ring gear, 12 bolt, Wide 5 spindles
Ring/Pinion ratio: 4:12
reverse pinion direction(from normal drive); R&P on right side facing quick change cover
Spool, both tires turn at same speed
10 spline Quick Change gears = 17/32 (0.53)
17/32 (0.53), is the tallest quick change set
bottom: big gear (shaft from trans), top: small gear (turns pinion)
both gears installed with shoulder around spline facing toward cover
run 17/32 for initial passes
Current final gear ratio = 2.19, 223mph @ 6100rpm hp max (assuming 6% tire slip)
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. . . also -- putting a smaller steering wheel than "stock" will quicken the steering, too. And in our case, this is often done to aid in getting in and out of the vehicle.
Stan,
we are evaluating alternatives to our current steering wheel, the top blocks a bit of our Racepak dash.
Maybe go back to a butterfly like Chaz had.
Karl
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I will have to noodle the reverse rotation---but is the eng rotation and the pinion/ring gear now both trying to lift the LF :? ---for traction purposes you most likely will need a bunch more frt weight---acceleration is now trying to unload your frt tires
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Entropy,
I did not see a response to my question regarding your 239 lbs of front lift. Is the 239 number what was seen at the wind tunnel speed (75 mph as I remember) or is it the calculated lift for 200 mph? Again if it is the observed lift at wind tunnel velocity then at 200 mph it would be 7.1 times higher, 1700 lbs!!! Just wondering.
Rex
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Entropy,
I did not see a response to my question regarding your 239 lbs of front lift. Is the 239 number what was seen at the wind tunnel speed (75 mph as I remember) or is it the calculated lift for 200 mph? Again if it is the observed lift at wind tunnel velocity then at 200 mph it would be 7.1 times higher, 1700 lbs!!! Just wondering.
Rex
Rex,
sorry to have missed that.
I am pretty sure that 200mph was input by the wind tunnel operator and that the results data, e.g. lift, is given in terms of force which would be expected at that number. Tom suggested 200mph; turns out he was very darned close.
Here's a thought: anyone who'd like a copy of the 2 page excel spread sheet of our results, please send me your email id
Karl
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I am pretty sure Torsens or TrueTrack available on several QC system
i finally had a minute...
wikipedia:
The Torsen differential works just like a conventional differential but can lock up if a torque imbalance occurs, the maximum ratio of torque imbalance being defined by the Torque Bias Ratio (TBR).[3] When a Torsen has a 3:1 TBR, that means that one side of the differential can handle up to 75% while the other side would have to only handle 25% of applied torque. During acceleration under asymmetric traction conditions, so long as the higher traction side can handle the higher percentage of applied torque, no relative wheelspin will occur. When the traction difference exceeds the TBR, the slower output side of the differential receives the tractive torque of the faster wheel multiplied by the TBR; any extra torque remaining from applied torque contributes to the angular acceleration of the faster output side of the differential.
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... so long as the higher traction side can handle the higher percentage of applied torque, no relative wheelspin will occur. ...
The Torsen can't fix all traction problems. As long as you don't overpower it I would think the car would go straight since neither wheel is spinning faster than the other even though more power is being transmitted to the ground through one vs. the other.
Overpower it and you can get out of shape just like you can with an open rear or locked one or other type of posi.
The open rear is the most forgiving in that it won't step sideways as fast as you still have 3 tires that have traction, but it is also the first to break a tire loose and just spin that tire and the car stops or slows acceleration.
Locked or posi rears are going to stay hooked up longer than an open rear but once they break loose then the back is going to want to take off in one direction or the other only to be stopped by lifting, the chute or hopefully the CG is ahead of the CP :-).
Another link for you...
http://www.maximummotorsports.com/Torsen-Limited-Slip-Differential-C157.aspx (http://www.maximummotorsports.com/Torsen-Limited-Slip-Differential-C157.aspx)
...and this should be the company but it wasn't coming up this morning...
http://www.torsen.com/ (http://www.torsen.com/)
Sum
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I would think the car would go straight since neither wheel is spinning faster than the other even though more power is being transmitted to the ground through one vs. the other.
Sumner--relative wheelspeed is not the determinant of whether the car will “go straight”. The tractive effort supplied by either wheel would be the pertinent quantity. If one side has 3 times the tractive effort, i.e. a 3:1 torque ratio, that will induce a yaw moment which will be seen as a tendency towards a direction change. As the torque ratio changes due to surface condition (traction) changes, directional “hunting” will be the observed effect. Any diff that biases the torque will, for this reason, produce this effect.
Clearly an open diff (a torque divider) would be preferred up until overall traction limits become a problem. Then it is a matter of adding weight or trading off stability for velocity.
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After reading this this morning---something occurred to me---in the last 30 years how much has changed with fwd cars they used to be horrible to drive in rain---some were down right dangerous-- I have seen many that had spun off the road during rain storms.
GM had a problem and then they programed the "system" to drop cruise control at the first sign of wheel spin. They were also working on no reverse steering inputs---ie wheel spin jerking the steering wheel---Karl you most likely do not want to have to put a late model steering system in your car. I would recommend a 40 to 1 ratio and pick as much of it as you can with mechanical advantage with the steering arm lengths.. YMMV
PS the reason so many FWD car manufactures choose the Torsen may be to keep the wheel speed the same is to minimize steering wheel jerk in hydroplaning situations
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After reading this this morning---something occurred to me---in the last 30 years how much has changed with fwd cars they used to be horrible to drive in rain---some were down right dangerous-- I have seen many that had spun off the road during rain storms.
GM had a problem and then they programed the "system" to drop cruise control at the first sign of wheel spin. They were also working on no reverse steering inputs---ie wheel spin jerking the steering wheel---Karl you most likely do not want to have to put a late model steering system in your car. I would recommend a 40 to 1 ratio and pick as much of it as you can with mechanical advantage with the steering arm lengths.. YMMV
PS the reason so many FWD car manufactures choose the Torsen may be to keep the wheel speed the same is to minimize steering wheel jerk in hydroplaning situations
Isn't this the reason to keep the scrub radius zero on front wheel drive?
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that is one of them but I think all cars will handle better with 0 scrub radius
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Man o' man, TFA received a ton of good discussion on our Lakester's handling issue.
Thanks to everybody! :cheers:
And that reminds me...
It's also time to thank SSS for maintaining landracing.com & encouraging the kind of participation we just experienced. :cheers:
I'm guessing i can find the "Thank You" button somewhere here
Next topic i want to get educated on is very high performance 260cid, V8 NA engines...
I am sure lr.com already has a great thread on that topic.
karl
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Easy answer, Keith Dorton, Automotive Specialist, www.automotivespecialists.com, 4357 Triple Crown Dr SW, Concord, NC 28027
(704) 782-0420.
Great guy, great motors.
Rex
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Easy answer, Keith Dorton, Automotive Specialist, www.automotivespecialists.com, 4357 Triple Crown Dr SW, Concord, NC 28027, (704) 782-0420. Great guy, great motors.
Rex
Rex, thanks!
their web site seems to be down but i poked around their facebook page.
Seems like they have been building motors for a LONG time!
What i am looking for is an education in D & E sized motors.
I am a complete novice about car motors and want to cure that ignorance. I know plenty much about the 1630 Busa motor, every facet of building. I am a one trick pony, but that detailed Busa knowledge should (might) allow me to at least ask a few 1/2 intelligent questions.
Max hp and build cost are obviously important, but max hp at the lowest build cost may NOT lead us to the BEST motor for us. It all starts with definition of our objectives, and those objectives may evolve as we see what the options are.
Basically, i want to build a big spreadsheet which captures all significant factors (w/pros & cons) which would play into selecting a much higher hp motor for our lakester.
My partner has some good experience & knowledge in this area and quickly starts talking about a D motor and even where he would source it. He is lucky to have this info.
On the other hand, his knowledge may be excluding a better solution. Probably not, but maybe...
I will just feel better about our new motor selection if i know exactly its pros & cons vs other options.
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TFA Racing had a great WOS event and my Partner & I are great buds, but last week he offered to sell me his 50% in TFA Racing.
Dang sure i bought it, but with Don leaving TFA, we have lost our fabrication guru :-(
Upshot is I need to quickly identify and engage a very safe, competant, available, innovative, cheerful, energetic, etc, fabricator (Boy Scout?).
A guy who says "4-6 weeks" and kinda means it.
Although i'd prefer he be located in Sugar Land, Texas, i will bring the car almost anywhere to the "right" person.
Any thoughts?
Karl
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Brian Bass, Bass custom is in the Big D. He has worked on Lee Sicilios Superbird and helps with a roadster as well as building his own roadster for the salt. http://www.basskustom.com/
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Brian Bass, Bass custom is in the Big D. He has worked on Lee Sicilios Superbird and helps with a roadster as well as building his own roadster for the salt. http://www.basskustom.com/
Thanks for the info Tman!
Karl
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Yep, Karl - :mrgreen:Brian would be a good choice. I`d love to do it, but shipping the car to Washington State probably isn`t going to work.....
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Paul........Don't pre-judge. Shipping it may be minor when
he gets good service and quality work.
I would hope he choses You.
FREUD
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I think maybe clear up one thing that at least I'm confused about.
Are you looking for someone who has a business that you can take the car to and pay for the service or are you looking for another crew member that has the capability to perform some or most of this work for no pay but possibly driving the car or if they have no desire to to that but only want to be part of a team effort and would like that opportunity?
Sumner
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True, Sumner. Since I make my living doing Metal Body Repair and General Antique/Classic Automotive Fabrication, I should have made it clear to Karl that there would be money coming from his wallet to my grimy hand...not that I would turn down a chance to be a partner/drive the car and work for free, but my mortgage wouldn`t get paid that way, and I can`t afford the divorce that would result from all those free hours...sigh...
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Sumner & KiwiPaul,
I'm sorry i didn't make it clear that i was looking to find a good person/shop to do fabrication for pay.
I sure realized the awesome good fortune i had going into Partnership with Don who has great fab skills. I 110% miss the ready solutions he'd turn out week after week.
After a lot of cogitation, i have decided to trailer the car to Delaware Chassis Works even though Joe's shop isn't exactly right next door to Houston to say the least. Our history trumps mileage :-D
kiwipaul,
Could you please give me contact info for your shop. First rate resources are difficult to find and i'd like to get you on my "yellow pages"
Karl
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Karl....Appreciate you thinking of me.....Kiwi Metalfab, Vancouver WA...(360) 607 9634...Email is
kiwimetalfab@comcast.net. If you want the physical shop address let me know and I`ll PM it to you...
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Karl,
If the Strange Days crew can be of any assistance let us know. We love that car....
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Karl....Appreciate you thinking of me.....Kiwi Metalfab, Vancouver WA...(360) 607 9634...Email is
kiwimetalfab@comcast.net. If you want the physical shop address let me know and I`ll PM it to you...
KP,
PM sent :cheers:
karl
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Karl,
If the Strange Days crew can be of any assistance let us know. We love that car....
Chaz,
Thanks much for the offer! You guys built a stout car which made possible our WOS adventure.
We were pitted next to Rex Svoboda's intimidating (his blower is bigger than our motor!) Saab 631 and he introduced us to Bill York who apparently was closely involved in your early build. Bill was GREAT to talk to!
Karl
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Karl....PM returned.....KP...
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Karl, are you going to use the same motor Next year?? :?
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Karl, are you going to use the same motor Next year?? :?
Fred,
hahahahahahah, i finally saw your question a month late.
Getting old isn't the reason, i've always been this way!
TFA is keeping the same motor/trans in 2015, I loved it's reliability and i am W-A-Y more interested in getting me 110% comfortable driving it than adding any hp. All 2015 work will be aimed at handling (maybe nothing wrong) and improving reliability (already real good). I am am VERY fortunate that Don got the car to such a good state for 2014, but i'm accutely feeling the vacuum left by him going on to other stuff. Time for little lil jaunt to Joe Timney in Dec/Jan with my car & mastercard!
2016 has some interesting motor possibilities, looking at 260 & 305" NA classes.
Karl
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Happy New Year to all!!!
TFA Update:
My #2 Son Daniel came home for Christmas, collected stuff from our 1st lakester experience at 2014 WOS (iphone pix & vids & in-car-camera), made a lil vid:
https://www.youtube.com/watch?v=-HGqwZAaJe8&feature=youtu.be (https://www.youtube.com/watch?v=-HGqwZAaJe8&feature=youtu.be)
Daniel wants to come to SW this year, says he'll gather his own material and make "a professional one". You are on Daniel!
Our car is now at Delaware Chassis Works for some of Joe Timney's magic. This project and all you people associated with it continue to keep TFA smiling.
Thanks to Chuck Kaparich for building the car and selling it to us, we are having a ball!
Next on the agenda is reservations at Montego Bay :-D
Karl
PS: If anyone has the link to the Strange Days construction slide show, we'd appreciate it
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Looks like it was hunting pretty good in the vid, do you have a toe issue or does it have a spool?
Sid.
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I was trying to watch the steering inputs by watching the brightly colored bolt head "down in the car" . Hand movement/steering input would be good info as your speeds progress sorta reminds me of the early RATICAL!
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KBT,
Both Don & I felt that it was "hunting pretty good", and the hunting/jinking sure spooked me. But neither of us MC guys have a basis for comparison, so the hunting may just be "normal".
The 1st order of biz at Delaware Chassis Works will be to make sure everything is straight and correctly aligned (including toe). BTW: it does have a spool; will that make it hunt?
Sparky,
Man o' man, your eyes are better than mine to be able to see a bolt on the steering shaft/reversing box on the fire wall. But your point is well taken about being able to see steering input. This year we'll somehow move the camera back so we can see steering wheel movement and I am mounting a piston on the steering linkage which will capture steering movement for the logging system.
I for darn sure have a lot to learn in this game and we are postponing upping the hp until 2016 to give me a chance to learn how to drive with more confidence in 2015.
Karl
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Cool car! Great video. It looks like you could use a vertical stabilizer. It should take care of that hunt and pucker. Congrats on getting it all together and looks like you guys are pretty close to getting the chassis optimized.
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:-D the operative word was "trying" lol
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You need to work on the problem at the front & not park a tail on to try & help it.
You first need to know where the toe is & be able to accurately adjust it at the salt to find the best setting for your car.
Having a spool will exaggerate everything & equal tire circumference is very important.
My inital thought looking at the vid was probably too much toe making it wash & the steering possibly too fast creating an over-input situation by the driver.
If it has a R&P, put a steering quickener in the shaft backwards to slow it down. If its a box, do a Pitman arm with multipul holes.
Make up a toe adjustment bar so you can do your own, just like an overgrown vernier caliper so it will fit up against the front & rear of both front wheels & measuer it right on center line. This system will give you an accurate straight ahead position & not off to one side where everything will change.
Sid.
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Cool car! Great video. It looks like you could use a vertical stabilizer. It should take care of that hunt and pucker. Congrats on getting it all together and looks like you guys are pretty close to getting the chassis optimized.
Rob,
Thanks!
For this year we are not going to really touch the aeros or motor, rather we are concentrating on making sure that the current basic set up is correct, change config & adjustments as needed, thus the lil trip from Houston to Joe Timney's shop.
Karl
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You need to work on the problem at the front & not park a tail on to try & help it.
You first need to know where the toe is & be able to accurately adjust it at the salt to find the best setting for your car.
Having a spool will exaggerate everything & equal tire circumference is very important.
My inital thought looking at the vid was probably too much toe making it wash & the steering possibly too fast creating an over-input situation by the driver.
If it has a R&P, put a steering quickener in the shaft backwards to slow it down. If its a box, do a Pitman arm with multipul holes.
Make up a toe adjustment bar so you can do your own, just like an overgrown vernier caliper so it will fit up against the front & rear of both front wheels & measuer it right on center line. This system will give you an accurate straight ahead position & not off to one side where everything will change.
Sid.
Sid,
Thanks much for your thoughtful and info packed post. From our previous discussions, you know my low level of knowledge of this stuff and I much appreciate you taking the time to push me up the learning curve
1. slow down steering:
We currently have a rack & pinion - Sweet Mfg, manual, ratio = 1 3/4. I am under the impression that this is a slow ratio, but Joe Timney will assess the situation. Stainless and others have also mentioned that slowing down the steering may help.
2. steering quickener (reversed): i had never heard of them, thanks!
3. home made "calipers" to adjust toe for our car's specific handling: awesome idea!
I have something close in my garage which i used to adjust MC rear wheel alignment. It may be possible to mod it to measure toe.
Thanks again,
Karl
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Four wheel drive trucks have had frt. strg. stab. for years
maybe and adjustable damper much like Rob but on his frt suspension---the racing surface is rutted and has humps and bumps---rear wheel drive cars and trucks "hunt" their way down the course---I am sure that would be magnified with frt. wheel drive.
Front wheel drive cars are notoriously dangerous on cruise control in the rain because of the changing tractive effort of each tire---a lot High HP front wheel drive cars have Torsens
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lots of sprint cars have "quickeners" which double the response of strg. inputs -- Speedway for one sells them--just install one of them backwards
at the speeds you most likely hope to run you may need some where around 30 to 1 by several's opinions on these forums
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lots of sprint cars have "quickeners" which double the response of strg. inputs -- Speedway for one sell them--just install one of them backwards
at the speeds you most likely hope to run you may need some where around 30 to 1 by several's opinions on these forums
SPARKY,
thanks much for the info!
And also thanks for your build thread, I am slil-by-lil reading the whole thing to help my education.
Karl
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Karl,
I run a Howe Racing "quickener" backwards on my little street modified and have probably 5-6000 miles on it with no problems. Works well.
Rex
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Thanks Karl,
Some appreciate it and others not so much---the reason it on here lumps, bumps, warts and all ---- is to help others at least be aware of what they (may/will) be dealing with. POSTING/READING is how I have become of some of my problems/solutions--- ymmv
there are lots that are willing to help those who are trying to learn thanks to all of them and to Jon A. / and Jon W.
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Karl,
I run a Howe Racing "quickener" backwards on my little street modified and have probably 5-6000 miles on it with no problems. Works well.
Rex
Rex,
thanks for the info! :cheers:
yesterday i learned that Joe T thought the car already had a quickener, and it seems like he favors them. Perhaps 5448 will come out of DCW with one. My wish list with DCW seems to be growing. (big surprise, eh?)
karl
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lol :cheers:
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Usually the quickeners are found in 1.5:1 and 2:1
They are hard to wear out, the round e round guys use them for years.
:cheers:
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Didn't look to be hunting too much, I have seen much hairier cockpit video.
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Didn't look to be hunting too much, I have seen much hairier cockpit video.
I feel it is real hard to pick up on video as to what something really feels like. I can see the tires/wheels going back and forth and it might not look like much but it could feel like a lot. Kind of like go out in a boat when the waves start to really build and you take pictures of them and then later the pictures don't look like anything. On the run where I thought the car was going to spin but the verticals caught it looking at the in-car or front view video it doesn't look like much but during the couple seconds and couple swings of the car it went from running down course on the far right side up against the markers to off the course on the left side running then with the left course markers on the cars right side. So in a couple seconds it move a considerable distance to the left but the videos don't show much of that unless you pay attention to where the course markers are.
If his wheels/tires are moving on their own as much as they appear I personally would want to improve on that and not just say I'll drive through it.
I guess the thing is are the wheels tires hunting on their own or is the car moving around and the driver trying to catch up with it when it might of just corrected itself and is that what we are seeing.
I only got to drive Hooley's Stude about 5 runs and it hunts a little overall but is an easy one hand on the wheel drive where you aren't correcting, just letting it do its thing and overall it is going to run straight but no video on the tires/wheels like that to see what they are doing while the car is hunting some.
Sumner
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I thank everyone for their input!
I am new at this but am trying to integrate your comments & advice
As tips are generated I keep track of them in the following list:
#5448 handling issue - (Put this material into pre-run visualization script)
FIRST: Assure all car's handling-related set up components are"right" (took car to Joe Timney Dec 15, 2014)
.9 do a low-medium progressive speed pass, see what low-high steering input does to the car at increasing speeds
1. minimize amplitude of course corrections, "it WLL come back"
2. Keep a light touch on steering wheel, gentle, smooth course corrections,
3. Both hands on the steering wheel equally, be careful during shifting & parachute deployment
4. Any movement of the eye can be translated into movement of the hands...
5. Feedback: ask an experienced TFA-sized guy make a pass in the car (Tom? Rex? Stainless?)
6. small heading changes without really changing the direction of travel that you need to learn to ignore
7. Tom sequence of "lane changing" see Oct 8, 2014
8. Wandering vs jinking, build into viz sequence
9. look way down the track, Do not fixate on cones/center line, heading should be established and maintained for these horizon landmarks
10. minimize handling issues associated with large power changes: weight transfer, torque reaction, yaw stability
11. tune the driver to recognize that lean angle was not directly correlated to vehicle direction and learn to ignore the lean angle and pay attention to the direction the truck was going
12. much of the activity normal folks make priority in the cockpit is not even necessary, or could be done in more efficient sequences to reduce overall cockpit workload and rushed feelings
13. "Do not step out of the throttle when they start to misbehave" "You need to consciously think about easing up, but not dropping the power"
14. Tom: " Once you get your “viz tape” sequence and the responses sorted out lets work through them and see how much improvement we can make before you even start practicing in the car"
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15. Move to Wyoming and drive in the snow every winter for weeks on end 8-),
Sum
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15. Move to Wyoming and drive in the snow every winter for weeks on end 8-),
Sum
LOLOLOLOLOL
I grew up in rural massachusetts and routinely drove "too fast for conditions" on snow/ice, only a few memorable miscalculations.
"Karl, slow down, you'll never make that corner"
(he was right)
karl
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Where in Mass? I'm in rural western end. 100 Miles west of Boston.
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Where in Mass? I'm in rural western end. 100 Miles west of Boston.
Chaaltun just west of Wusta
As I used to say it