Landracing Forum
Tech Information => Aerodynamics => Topic started by: Sumner on November 30, 2013, 12:22:50 PM
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Nice!
Let's see some more if that car!
Here ya go!
(http://www.landracing.com/forum/index.php?action=dlattach;topic=12393.0;attach=44169;image)
A beautiful car and it looks to have a lot of potential with that body shape. I looked in the Speed Week results and couldn't find a time. Did it make a run? If it didn't please post results in the future,
Sum
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Sum,
We went to the line twice but didn't make it to the clocks. First time we didn't have the engine tune up right to start and idle without running them against the clutches. Second time with the engines starting and idling nicely we found we had burnt the clutches in the first attempt. After a multi year build on both the car and trailer we were happy to make it there with no problems, pass tech with no major problems and actually turn a wheel on the course.
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Do you have more pictures of the car without the body and with? From where the exhaust is exiting I'm wondering if it is front engine/front wheel drive?
If you get the motor sorted, I'm sure you will, I'll bet the car does very well,
Sum
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The body is beautifully done ----------------- smooth! :cheers: :cheers: :cheers:
What is it using for power?
More pics with the body off would be great. :-D :-D :-D :-D
Pete
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(http://purplesagetradingpost.com/sumner/bvillecar/K-GS%20628-1.jpg)
Also interested in the canopy. Did he make it or buy it?
Sum
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2 go kart engines. 125s if i remember right. im trying to load up the pics i have.
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file too large . 1.5 mb jpeg . SSS , what can i do to these pics to get em posted ? do i gotta do the photobucket thing ? :?
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If you are storing your pictures in the Pictures folder on your computer, just click on the picture you want and at the top it will say "edit", click on the edit button and a new window will come up, usually Windows Live Photo Gallery. Then just click on the picture and at the top it will say Properties, click on that and it will say re-size, click on that and it will let you re size your picture to a smaller size. You can play with it to find out what works best, but as I recall the maximum attachment size allowed is 500 KB per post.
That is what works for me.
Tom G.
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If it is 800 x 532 and size above 100kb is fine.
You can post as many as 4 images but the total size can not exceed 500kb.
FREUD
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think i got it
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and another
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Good, but... :-D
Bigger is better. Professor Freud suggested 800x532.
Just sayin'.
Mike
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like this ?
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The gloss on that paint must be good for at least 10 MPH...
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Good, but... :-D
Bigger is better. Professor Freud suggested 800x532.
Just sayin'.
Mike
:-D :-D :-D :-D
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What a beautiful car.
Like everyone else said, the body and paint is perfect. :cheers: :cheers: :cheers:
That is one serious packaging job. It's unbelievable they managed to massage that much equipment into such a small area.
If the builders decided to get into shipping and freight handling they'd change the world.
Awesome stuff and congrats to the team.
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Also interested in the canopy. Did he make it or buy it?
Sum
We made the plug, then the body mold, then a form for the canopy offset inboard by the canopy material thickness. That form went to a vacuum forming company in LA.
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How long is the car?
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Very cool car! :cheers:
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Also interested in the canopy. Did he make it or buy it?
Sum
We made the plug, then the body mold, then a form for the canopy offset inboard by the canopy material thickness. That form went to a vacuum forming company in LA.
Thanks, do you have a name or link for them?
Also any more about the drive train you can tell us about or pictures? I'm thinking front-wheel drive or a drive shaft to the rear?? Also if the engines are two 125's then you are giving up a lot of cc's aren't you?
I'll for sure try and find you and the car on the salt next year,
Sum
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Thanks, do you have a name or link for them?
Also any more about the drive train you can tell us about or pictures? I'm thinking front-wheel drive or a drive shaft to the rear?? Also if the engines are two 125's then you are giving up a lot of cc's aren't you?
I'll for sure try and find you and the car on the salt next year,
Sum
http://www.aircraftwindshield.com/
It is front wheel drive, theoretically there is enough space to cram in two more of the Rotax 125 cc engines. We pit with my club the SDRC.
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I certainly agree with everyone else that is a pretty car! It just makes me more disappointed that I got sick at Speed Week this year and had to go home early so I missed your car!! The K record is held by Jim Burkdoll at 202 mph for the gas record and Brant/Spranza at 180 for the fuel record (this was with their old body configuration) so you have some pretty tough targets to shot at.
Good luck and looking forward to seeing your car next year!!~!
Rex
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Rex,
Sorry to hear you had to leave early. Jim Burkdoll came by, looked us over and paid us the extreme compliment of saying that this was the first car he had seen that looked like it might take his record away. While I value his words we still have to proof this pudding.
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How long is the car?
202 inches
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If you can get 4 of the Rotax 125s in there then you are going to have some pretty serious horse power! Some where between 150 and 200 probably which should make your car a VERY serious contender!
How about a pic of the engines.
Rex
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Here you go
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Oww! My skinned knuckles hurt just looking at that. Good work - but not for my fat fingers. . . :-D :-D
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I still like the roadster better.
Well -- I'm prejudiced. I think that means having an opinion without real sensible backup.
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I still like the roadster better. :roll:
SB,, does that apply to 34 roadster pickups running in Fuel-Gas??????????? :?
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I still like the roadster better.
Once a roadster guy, always a roadster guy. :-D
Beautiful car, wish I had been up at SW longer to have seen it. Next year!
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I still like the roadster better.
Well -- I'm prejudiced. I think that means having an opinion without real sensible backup.
Well Stan since the roadster is mine and the streamliner is Mikes, I like it better too. I am assuming you mean the street roadster not Ken and I's modified.
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I like the modified.......... :-D
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Regarding Aircraft Windshield, I used them and I couldn't be happier. :cheers: Super service and product. Wayno
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Jim, is this still rear steer???
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yep
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Jim, is this still rear steer???
:-o :-o :-o :-o :-o :-o :-o :-o :-o :-o :-o :-o
Yep.... OK, time to dish out a little more info here boys....
I thought back in 1980 the rules were changed to say a car steers with 2 front wheels.....
Although I know some guys with some RWS experience, in a K streamliner....
So how is it going.... we need to see how you are making it work
Yes, I do know that the fastest car in the world steers from the rear....
I would like for somebody to show it will really work... last guys kept tipping over... last time it tipped over about 6 times before it stopped.
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Stainless,
You of course are right, if we run a record speed it will not be certified as we do not meet the definition of a "car". You may or may not remember back in 2007 I surveyed you, the guy on the east coast with the roadster and Donnie Johansen regarding experiences with rear steer. We are not replicating any of that engineering. After a careful perusal of all available data on the rear steer jet car we decided to go with that design. That being no caster, an EXTREEMLY rigid mechanisim and ZERO play in the steering linkage. While we have had it past 60 MPH on the dry lake bed we still have to prove that it will work. The SCTA has set us a series of milestones to accomplish before they will take the yellow tag off and we had to apply for and sign a hold blameless waiver regarding both the rear wheel steering and front wheel only brakes.
You might ask why we would go to all this trouble when we can't actually set a record. As Dan is fond of saying it isnt a bucket list item it is a lifestyle. Lots of people told us it wont work but no one says why (One engineer told us it wont work because it totaly depends on rear wheel traction to steer). We aim to find out.
Also Mike wanted a design with a minimum frontal area to enclose a supine driver using published design data for a minimum drag body. We have paid close attention to pressure recovery, area progression and keeping all surfaces to their design specs. The outer skin defines the car.
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Rear steering works. 2,500,000 forklifts can't be wrong.
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So what kind of drivetrain are you using? Is that a t-case I see in the picture? A friend and I been pondering a front wheel drive streamliner for the last year, and have finaly started gathering parts. Just wondering what type of setup your using.
Cory
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Rear steering works. 2,500,000 forklifts can't be wrong.
With front wheel brakes as well. I had some "fun" moments getting used to driving some of those set ups though.......
Ed
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A friend and I been pondering a front wheel drive streamliner for the last year, and have finaly started gathering parts. Just wondering what type of setup your using.
I suggest that you also gather up some sort of overrunning or freewheel for when you let up or blow up.
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Well you have my attention! I look forward to seeing it go record speed, and I hope that the SCTA waives that rule for the car, made specifically because our attempt at rear steer was not too successful, and certifies it for that record.
If you can make it work with rear steer, it is a 4 wheel vehicle and has 2 wheels steering, it is car... Buckminster Fuller would be proud of you.
:cheers:
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Well you have my attention! ..
Mine too!! I use to have a ...
(http://3.bp.blogspot.com/-mvuF0vIK2CM/Tk63VyO5xZI/AAAAAAAAILI/W0JprAS9k1A/s1600/Big+Hole+Buck+Rake.JPG)
...motorized buck rake, similar to the one in the picture above. It was use to pickup loose hay that was a converted late 40's GMC truck where they flipped the axle and mounted a seat backwards and had the hydraulic fork mounted over the rear axle and you drove around backwards with the front wheels now the rear wheels/rear steer. A very interesting vehicle to drive at times especially since they didn't 'flip' the steering and you steered right to go left.
One thing that I think would really be different on the salt is you need so little steering on a run that you could really limit the ability for the wheel to turn much and set it up with slow and limited steering input.
I was really hoping the streamliner was front wheel drive and steer. I wanted to see how the common jackshaft was made with custom ends and spindles to do that.
It will still be a very interesting car to follow and hope the best for you guys,
Sum
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Neat little car, I saw it at a distance at Speedweek. Wish I would have taken a closer look.
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What is the weight distribution?
All of the engine, fuel, and water is in front of the front tires.
That is unloading the rear tires at the same time.
You can always add weight to gain steering authority, but that's extra weight to drag. Very different from adding weight to gain traction.
Is there a differential?
That very long exhaust tube after the expansion chamber? Why not exit at the stinger?
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What is the weight distribution?
All of the engine, fuel, and water is in front of the front tires.
That is unloading the rear tires at the same time.
You can always add weight to gain steering authority, but that's extra weight to drag. Very different from adding weight to gain traction.
I feel his setup is actually a lot better for overall weight. With a rear drive car you are adding weight for traction usually but also a lot of weight that does nothing for traction and isn't needed for steering. Only there to keep the CG ahead of the CP. I'd say with Hooleys car over 50% of the weight we have had to add is there just for the CG part.
Rob of course is trying to go light and use controllable aero downforce on the back of his NACA 66 Special streamliner which could also be a good deal vs. carrying all of the dead weight we do and might possibly work for us once we get more comfortable with using the rear wing or a new one.
I think one of the major things you have to handle with a front wheel drive car is the one Sparky mentioned,
Sum
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What is the weight distribution?
Is there a differential?
That very long exhaust tube after the expansion chamber? Why not exit at the stinger?
Dean,
Weight distribution is 67% front 33% rear, center of pressure is behind the CG.
There is no differential.
We wanted to add energy to the boundary layer in the aft half of the car to aid in reducing drag.
Sparky,
Centrifugal clutches, no power no connection engine to drive wheels.
Sum,
We have provisions for changing the steering ratio. We thought we might want to slow it down as we work up in speed.
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If you don’t qualify for SCTA records, how about going for glory with the FIA?? 8-)
The current up to 250cc NA records look a little soft at 122 mph (kilo) and 120.116 mph (mile). At least I assume they’re soft since they were set at a couple of British airfields.
[Actually, I've just noticed that the 250cc to 350cc records (flying kilo and mile) appear to both be ‘Open’, and the 350cc to 500cc class are only 99.5 mph (kilo) and 88.7 mph (mile).]
Even the blown records may not be out of reach:
Up to 250cc – 144.2 mph (mile and kilo), set in 1959
250cc to 350cc – 158.2 mph (kilo) and 158.3 mph (mile) set in 1966
350cc to 500cc – 222.6 mph (kilo) and 223.1 mph (mile)
OK, so the last two are a bit more challenging, but once you’ve got the first ten you might be ready aim at 225+mph. :-D
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Maybe 2,500.000 fork lifts can't be wrong but not many of them can go 200 mph either!! Maybe a new SCTA class!
Your approach to rear steer, in my opinion, is certainly correct, a very ridged (stiff) steering mechanism with zero free play to reduce/eliminate any ability for the rear steering wheel to oscillate along with zero caster to eliminate any induced steering loads all look like good thinking. I would also suggest, if you haven't already done it, a very stiff, probably hydraulic, steering dampner that is designed to provide a small amount of dampening at normal steering input speeds but lots of dampening above that level, and I would attach it directly to the steering mechanism at the steering wheel. If you can keep it stable it should work.
Just for my info what wing section shape did you use to form the body to?
Rex
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Rex,
I am not sure of the number/name of the profile. It is not a wing section but a sailplane fuselage shape. I could ask my brother if it is important to you.
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If you could, I would really appreciate it as I am always looking for new aero shapes. I personally like the NACA 66000 series but the sail plane people have done some great things when it comes to low aero drag. Ask your brother if part of your aero package is "Natural Laminar Flow" considerations.
Rex
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Rex
Re: airfoils, did you follow up on Prof Selig and the U of Illinois work I mentioned a few years back?
Some interesting laminar flow shapes, some that would accomodate a Lakester package especially.
Back to the K Streamliner, the shape resembles Soap Box Derby design of the '50s somewhat.
Simple to fabricate, but slippery.
About rear wheel steering, many know Mickey Thompson dabbled with it (with normal front) for Indy.
Mickey took a friend of mine in the Toronado he had adapted for evaluating same.
Abrupt lane changes at speed on the Long Beach Freeway!
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I thought soap box racer as well when I first saw it! :mrgreen:
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When I was in high school the auto shop teacher built a kart with a lawn mower engine.
It had rear steering. But to make it exciting, the steering was backwards, turn left to go right. Hilarious to watch.
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"...turn left to go right..."
That's like what you do when backing up a trailer. I've learned to think of it, instead of left gives you right, that the trailer is going to go the way that the BOTTOM part of the steering wheel is going. It makes backing way easier.
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Is that a 1-inch thick aluminum plate on the bottom, or something else? This car sure has me interested in switching to 4 wheels.
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That one was a fiberglass/foam/fiberglass sandwich. It has been replaced with aluminum/aluminum honeycomb. Bad material selection on the first one resulted in delamination.
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I look forward to seeing you chain them in there like "Galley Slaves" :-D
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Before you convince yourself the centrifical clutches will release from engine to drive train think about how that will work. If the engines are turning 10,000 rpm so is the output from the clutch. If you shut the engine off the output of the clutch driven by the wheels will not release the engine as they are both turning the same speed. The clutch won't release until both the engine AND the output slow to the engagement rpm. Ask the clutch manufacturer if they agree.
Jim
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Interested Bystander,
Wasn't Mickeys four wheel steer? Never mind I re read you post and that's what you said.
jauguston
These are go cart clutches with springs and shoes that are not self energizing, they disengage quickly enough to get a clean plug reading.
Sparky,
An apt analogy indeed, It certainly is going to be dark, hot and smelly in there.
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I share Jim's concern about clutches not releasing.
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Had a great test session at El Mirage yesterday. Russ drove down from Salem bringing the quad we are going to use as a push vehicle. We tested without the body as we weren't sure the scheme was going to work. Probe on the front of the quad engages a tube on the chassis above the chute cans. The chute doors are spring loaded so they will close when the liner pulls away from the push. I was able to push the liner up to my personal speed limit with no problems. We made three passes of about a mile each with Russ getting up to 82 MPH, slowing and making a big loop to come back to the starting point. We also tested a tow attachment to the front of the quad so we could tow it to the staring line behind the liner trailer. Russ also tried wearing my son's NecksGen head restraint, no problem strapping in or bailing out. We want to change to this type device as the Hutchens type we have is just too much of a pain to get him strapped in being sure that the multiple straps are properly placed and tightened.
Clutch release was not a problem, I sure hope speedweek comes to fruition.
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Looking good.
That blue must be the team color -- looks great!
Good seeing you Saturday -- I was a little pre-occupied.