yu888

When Gilcwong and I took the performance course at Sears Point raceway earlier this week, the first thing they did when they prechecked our cars was pump up the pressure in our S02's to 50-52psi! Seeing that the max rating is 44, I was wondering how long one could run like thatbefore problems occur. I have already lowered it back to 37-40psi, but I am just curious since we did 30 laps with the pressure high like that. Comments for anyone experienced with track drivng?

Allan Haggai

The max pressure listed on the sidewall is a cold maximum. The tire is safe well beyond that to allow for increased pressure that will build up as temps rise, but I'm still surprised that they started you guys at 50 psi cold! That means you hot pressures could exceed 60 psi. Most S2K guys run 36 - 38 psi cold at the track.

Penforhire

Yeah, that pressure is way too high! 42-44 seems like the top end in Auto-X and you run less pressure than for Auto-X at most tracks.

Seems like 50 PSI would make the car drive nervous at both ends.

yu888

I may have found the answer today talking to Krazik. According to him, or what I got out of what he told me is: Track schools increase the pressure in the tires (for insurance) to make it harder for us to go faster and to keep the cars from rolling. Higher pressure makes for less stickiness and less likelyhood of sticking when the tire hits the limit.

I did notice that the tires were providing more continuous feedback about approaching its limits than usual. Anyone with other answers pls let me know...

DavidM

At every driving course I've been to they recomended pumping up the pressures to 50psi. I had the pressure up there and things were fine ... in anything I suffed less tyre wear.

Also, my father is running 235/45/18" S02 tyres on his car and he totally shreaded (literally) the rear tyres around the sidewalls while doing a cross-country trip (high speed trip, around 180 - 230km/h was common cruising speed). He was running 37psi and these tyres pretty new before the trip. The dealer (and tyre people) told him that the pressures were way too low for that kind of driving and told him to put in good +10psi in there. Right now he's running 45psi in city driving and if he goes on another trip like this then he's pumping them up to 50psi. btw, he's been running 45psi for good 6 months and the tyres are wearing (and handling) nicely.