URGENT: Recommended Track Tire Pressures

[Vudu]

Hi,

I'm going on a timed track session tomorrow with my 997TT and I was wondering if anyone could recommend the ideal tire pressures in PSI for my Pirelli Corsa's (same size as stock). I had a quick practice session today on the track using standard pressure settings (34 front 40 rear) and I didn't notice a huge difference in grip compared to my stock Rosso tires. I've heard some guys using even less than 30 psi on the fronts and close to 30 on the rears.

Can anyone give me a heads up about this? Is it safe to drive on the track with tire pressures that low? Obviously the pressure will increase with temperature increase, but what are the ideal numbers I should stick to??

Any help much appreciated! Preferably before tomorrow! :notworthy:

Thanks!

[david_yorkshire]

not a TT, but a 2S on the same tyres;

I had mine adjusted to 26psi cold all round by a well known motorsport company on a trackday I did last weekend.

Made a huge difference - the car was totally neutral.

and no, don't drive on the street with these pressures !

you need a lot of heat in the tyres for this to work.

[Camus997]

This is an important issue! After much advice and experimenting, I'm running (HOT PSI, after a few laps) 38 front and 40 rears. This may vary depending on your tires, but I'm running stock PS2s.

Good luck, and keep safe.

[Dus10R]

Hmmm...28Psi... I use a Tire Pyrometer to adjust tire pressures via the temperatures that run across the face of each tire (outside, middle , inside)

Last year I noticed that running OE Reccomended pressures caused the middle tire temps to be a lot higher than the avg of the outside and inside temps, which means to much air. I got the fronts down to 28psi which was the lowest pressure I felt safe running and the middle temps where still slightly higher (10 degrees) than the outside and inside temps. The rear I lowered to 36psi and the middle and inside temps were about the same (negative camber) with the center being slightly higher in some runs. But the fronts gave me pause. According to the tire temps they needed to come down in pressure even more but I just wasn't sure how low I could run them without risking the tire comming off of the wheels.