LR Tire wrinkle?

[missile07]

You see so may cars whether its late models or modifieds with the LR tire wrinkled on the ground. Is it the load being applied or lower air pressures?

[Highwayman]

You ever watch drag racing? Same thing, it means the tire is really hooked up and biting the ground hard. Essentially the tire is so well planted that the engine torque is twisting the tire and causing the sidewall to wrinkle.

[TheJet-09]

I wonder if he meant while the car is static, just sitting there, or in motion around the track? I've thought about this looking at pictures of cars racing (the common infield shot). Some cars have a bit of wrinkle to the LR, and others don't. Without citing specifics, it seemed to me the fast/er cars did not have any noticeable wrinkle in the LR when on the gas.

[Lizardracing]

Funny story. USRA modified class where bead locks only allowed on the RR and RF.
Tech guy at a local track went around spray painting wheels. Say's he was looking from traction lock devices and illegal differentials. When I asked him how many he caught he says he knows that used to be the thing to do and how big of advantage it was and blah blah blah. Anyway...after the heat races about half of every ones tires had spun on the rim inside the tire nearly half way around due to low tire pressures and tacky race tracks.

[missile07]

In the link look at Pierce & Bloomquist. Some of the Bloomquist photos have it and some don't. We have run as low as 6lbs, are teams going lower than that ? You can look at a few others too...McCreadie & the 91

http://lucasdirt.com/series-media/photography/collection52799742-72157663590070784/set72157669614108342

[CCHIEF]

It's load, at that moment.

[TheJet-09]

6 psi in the LR is where I start the night at. I would think starting with something as low as 4 1/2 psi in the slick is not too uncommon.

[Basecircle]

If your car is on the bars, and off the spring, the tire IS the spring. I would say as you hit any little bump the sidewall would wrinkle more and then balloon up and not be wrinkled. The same car would change appearance as it goes around the track and through any bumps.

[a25rjr]

Less air pressure doesn't equal more traction. Sometimes, less footprint makes more traction.

[dfhotlm33c]

Tire pressure and sidewall construction...6 psi on a C4000 88/11 will usually show a some wrinkle at rest. The stiffer and smaller 90/11 tires at 6 don't usually show that wrinkle. Lost of factors, but that has a lot to do with it