29.0's on LR

[fastford]

https://www.google.com/search?q=glea...hrome&ie=UTF-8

There very interesting, always wanted to tinker with one.

like i said , it didnt like stagger and back then on a tight turned track , i couldnt get the throttle push out of it , but things are different now with all this dynamic roll steer , one of the fastest laps I saw last year ar TST was with a spool and 1inch stagger , so it might help on over all forward bite over the spool , dont know.......

[billetbirdcage]

On dirt around 10% slip is average so how do you account for that?

Typical wheel spin % is much much higher then that, in my testing back 25 years ago (before it was illegal) with real censored traction control 10% was too low to produce the fastest lap times. Dropping the wheel spin typically tightened the car, so if you started limiting the wheel spin you ended up adjusting the car. However once you got down to around 13% no matter if you adjusted the car and tried lowering spin % you weren't going to lower the lap times. It took a lot of work to get faster times under 15 to 18% and you had to really work at it. I assumed years ago when I was doing the testing that 13% or so (for our tires at the time) was the minimum slip angle the tire needed to produce maximum traction. You would be shocked if you saw the actual % of un-managed wheel spin on a Late model.

[billetbirdcage]

https://www.google.com/search?q=glea...hrome&ie=UTF-8

I can't say if the one afco had years ago was exactly the same but it was a gear type design, but one of the Hav-a-Tampa regulars did a fair amount of testing with one until:

I think it was Dixie back around 96 to 97, when he was running the low line and letting the car drift out to the wall on the straights. It had a ledged cushion against the wall some even on the straights, when he drifted out to the wall coming off the corner and banged the cushion with the RR, it unlocked and tried to drive heavily with the LR and nosed the car into the wall and took him out while leading the race. He took it out after that and said F' that.

Not sure how prevalent that is now a days with the newer stuff but I can see how you might end up with some issues.

[7uptruckracer]

I’ve never done that kind of testing sounds cool, just basing that number on what I was told by a higher up that at least 10% but maybe the a least is much higher. Or it could have been referring to asphalt not sure I do know I have seen someone install a Davis Traction Control system and it did a lot of what you said it tightened the car up and made it slower by about .2 but sounds like interesting info

Typical wheel spin % is much much higher then that, in my testing back 25 years ago (before it was illegal) with real censored traction control 10% was too low to produce the fastest lap times. Dropping the wheel spin typically tightened the car, so if you started limiting the wheel spin you ended up adjusting the car. However once you got down to around 13% no matter if you adjusted the car and tried lowering spin % you weren't going to lower the lap times. It took a lot of work to get faster times under 15 to 18% and you had to really work at it. I assumed years ago when I was doing the testing that 13% or so (for our tires at the time) was the minimum slip angle the tire needed to produce maximum traction. You would be shocked if you saw the actual % of un-managed wheel spin on a Late model.

[Kromulous]

I think it was Smokey Yunick that said the best you could hope for on dirt was 30% slippage, not sure but i remember reading that number somewhere. Seems plausible i guess.

[fastford]

Typical wheel spin % is much much higher then that, in my testing back 25 years ago (before it was illegal) with real censored traction control 10% was too low to produce the fastest lap times. Dropping the wheel spin typically tightened the car, so if you started limiting the wheel spin you ended up adjusting the car. However once you got down to around 13% no matter if you adjusted the car and tried lowering spin % you weren't going to lower the lap times. It took a lot of work to get faster times under 15 to 18% and you had to really work at it. I assumed years ago when I was doing the testing that 13% or so (for our tires at the time) was the minimum slip angle the tire needed to produce maximum traction. You would be shocked if you saw the actual % of un-managed wheel spin on a Late model.

I remember reading a article on bloomer testing traction control back several years ago and he was like 3/10ths faster with out it , I may be wrong , but I think some wheel spin is faster than none...

[let-r-eat]

Yes. You definitely need wheelspin IME. RPM X Final ratio you are running and then compare that to your actual speed on the racetrack. You'll see most cars running around 100MPH actual speed on the track has a gearing that puts them somewhere between 120 to 150mph. Depending on rollout you could calculate the slippage. There is an enormous amount of information that can be used in knowing those numbers. Not all track surfaces are the same.

[a25rjr]

I can't say if the one afco had years ago was exactly the same but it was a gear type design, but one of the Hav-a-Tampa regulars did a fair amount of testing with one until:

I think it was Dixie back around 96 to 97, when he was running the low line and letting the car drift out to the wall on the straights. It had a ledged cushion against the wall some even on the straights, when he drifted out to the wall coming off the corner and banged the cushion with the RR, it unlocked and tried to drive heavily with the LR and nosed the car into the wall and took him out while leading the race. He took it out after that and said F' that.

Not sure how prevalent that is now a days with the newer stuff but I can see how you might end up with some issues.

I know one HAT car owner that ran them quite often.

At one particular track, his driver had a 1st and 2nd. Funny thing is, all the other cars were 4bar, and his was mono-leaf with coilovers!