Spin Question

[interested bystander]

Looks like this is becoming one of those blind men and the elephant topics!

Hey, Landracing I weren't DONE!

Stan didn't mention his near 194 ElMo record or the easy 190 pass this year @ the same event the former BV record holder did another of his spins.

I are done now!

[Kiwi Paul]

I posted some thoughts on this somewhere else on the Forum, but since Shaen Magan`s Street Roadster was mentioned, I can tell you that the crew were very excited to be able to apply some chassis preload to the rear four link, along with a sprung (changed from solid) rear end and a taller gear, and were able to get the car through the 5 for the first full pass, instead of having it spin repeatedly at 215-220. I don`t think this is a cure-all, as all roadsters really vary ALOT and Stan Back`s experience is just as valid as Shaen and crew, but after helping with reinspections at Speed Week this year, I can`t help but observe that alot of those Roadster spins are happening at about the same mph.......anyone else?

[Roadster943]

  Ok here I go. Stan Back is one of my best friends. What works for him is not what works for me. He has more records than I will probably ever get But! My roadster has no rear suspension, I run 70psi in one rear and 60 psi in the other. I have 12 passes between 200 and 215, ( not many) I run a spool. I have never spun. 3500# when it leaves the line, heavy on the rear, close side to side. I have heard the story of roadsters becoming evil when you run out of power. This has never happened to me. Best pass 214 the next day 215 with a 216 exit I thought she was wanting to kill me. My car is center steer. The fastest roadster in the WORLD has NO suspension. Vintague Hot Rod has been running roadsters for 20 years and never spun, no rear suspension ever. Al Teague ran 267 in about 74 with a stock wheelbase stock body Model A with a solid mounted rear end and a buggy sprung front end. Stan is right, Al Teague is right, Vintague Hot Rod is darn sure right and I am right. We all have Red hats in roadsters and all got there with something different. I set my car up with a tape measure and a plumb bob. Scrub radius? other things mentioned here. beyond me. Lean the front axel back as far as you can, make sure it is square, make sure the rear tires have the same runout, and sorry Stan put a spool in it. I have found with my car if the steering wheel is doing something more than providing my left hand something to hold onto it is not going to be a good pass. When the starter tells you to stay to the left or right side of the course just smile and remind yourself its a roadster and that the goal is to go through the 5 between the markers, pointed the right way and your foot IN IT. Ten people are going to tell you I am on Crack.  Good Luck Vince

[jimmy six]

Vince. Congratulations on your "hat" and doing it with a Skinner/GMC. I think that's 7 of us all with a little help from Joe.

I agree with the center steer; it's been working on our car since 1971. We have used solid mount with a spool, coil over with a spool, parallel leaf & open and only spun because of stupidity of the rebuilder (me) at 185. We keep the movement on the rear axle to 1/2". Only ran out of hp once and I had that ride but did not spin it. Hopefully we will see 200 again but 170 you are right about a place to rest you left hand while waiting for the finish. If they are right they are a pleasure to drive.

Once again congrats on the hat......(Skinner with all the trimmings on the shelf too).........................JD

[Richard 2]

Am I the only one who has extreme issues at the 3 1/2 on the long course?  This happens at around 195 and I have short shifted or coasted for the shift in that part of the course to try and avoid a HARD snap to the left.  We added 500 pounds of lead in the back in attempt to avoid this, but I'm afraid this might be destroying the "lawn dart" effect that may have kept me from crashing before.  I guess I'll see in September!

I'm done Shifting when I pass the 1 mile marker and I always know I'm going to have turbulence at the 2 1/2 and the 3 1/2 when I'm over 210 mph (under 200 mph its just a sunday drive). I've been told it's a wind vortex blowing between the mountains. One spin at the 4 mile at 222 mph in 2010, spool, loose salt, HP, and too lite in the front, I think. Added 130 lb to the front, behind the front axle, help handling alot.
Richard

[Stan Back]

Vince is right.

I've experienced the "notch" once years ago.  I think it's real.  And the location varies with the course layout and the wind direction.  I stay to the left all the way down (if I can), 'cause it takes you to the right.

But I guess my point (not very well made) is that simply adding weight and measuring side to side and front to back and calculating wind resistance side to side won't fix a car that has inherent problems.  A case in point was a new roadster I observed at SpeedWeek.  Scary at 130.  Very well constructed with high-grade street rod parts.  Thousand pounds more than ours and they were gonna add weight to fix it.

I also subscribe to AKK's formula expressed here a few months ago -- and their results sure speak for how it works for them -- keep adding weight 'til it won't spin the tires in 3rd.  Led to real funny weight distribution (80/20 in AA?) and their own page in the Rule Book.

As JD says,
"Good Luck"

Stan Back

[Roadster943]

Vince. Congratulations on your "hat" and doing it with a Skinner/GMC. I think that's 7 of us all with a little help from Joe.

I agree with the center steer; it's been working on our car since 1971. We have used solid mount with a spool, coil over with a spool, parallel leaf & open and only spun because of stupidity of the rebuilder (me) at 185. We keep the movement on the rear axle to 1/2". Only ran out of hp once and I had that ride but did not spin it. Hopefully we will see 200 again but 170 you are right about a place to rest you left hand while waiting for the finish. If they are right they are a pleasure to drive.

Once again congrats on the hat......(Skinner with all the trimmings on the shelf too).........................JD

  Thanks JD means a lot coming from you. There is not another group of people on earth I would rather be assosiated with. Joe is a treasure, he was in my push truck when they sent me off on my return. See you in October.  Vince

[Glen]

The Jesel roadster spun every run at speed week and they said they can't find the reason and will retire the car. BTW, it spun to the right each time.

[Stan Back]

Tell you what, I'll ask Wayne if he wants us to test the motor and see if it's the problem.

Stan Back

[jl222]

The Jesel roadster spun every run at speed week and they said they can't find the reason and will retire the car. BTW, it spun to the right each time.

  It just might be this years course conditions or wet or loose salt, the 222 camaro has always felt comfortable at speed 200-300,
 [glued in], this year no traction and felt real loose, like it could swap ends at any time and did

  Data logger shows 100% throttle in high gear last year and 318mph at end of 1st mile. [294 avg]

  This year 48% throttle and spin at 270 -280 mph.

  We took videos of data logger and if they come out OK Bville will post in our build diary and maybe here to show course conditions.

            JL222

[Glen]

JL
This car has a history of spinning, last year was the only year it didn't spin. They thought it was fixed but the problem returned this year. A lot of people looked at it with no understanding as to why. I talked to Wayne and it's to the point of being dangerous as it was up on two wheels this time when the chute caught it.

[Kiwi Paul]

Glen--Since Wayne is going to retire the car, have him give it to you. Then Stan Back and yourself could discuss and implement the necessary fixes. I`d volunteer to drive, if needed....

[Dynoroom]

I wouldn't count on the "retirement" of the Goldstrom & Jesel street roadster. It is very unlikely a team with the resources and success in other classes will throw in the towel, just rethink the problem would be my guess.
As has been stated, many ways to skin a cat er... roadster.

[Kiwi Paul]

Which would be my point, actually....

[thundersalt]

Have they tried different drivers? Just a thought, don't want to upset anyone.