Weight on front and rear

[JayG]

Originally Posted by steved0x

When I first got started with HPDE I thought that as long as you didn't roll over on the shoulder you were good. I didn't realize that by the end of the day my hot pressures were up in the 40's and I wondered why I was sliding around like crazy. The first time I had a "hot" session with my tires right in the sweet spot (around 32 front and 34 back hot, 225/45/17 and 255/40/17 Hankook RS3) I was like WOW. What a difference. A friend has a 996 with PS2s and ran these really high GT3 pressures and did not bleed throughout the day sp he was wickedly high in the 40's, once I got him to bleeding he was like WOW too and ran his best times.

The downside is airing them back up for the drive home... if it is a long drive like 3 hours they will cool back down and go below 30 if I don't give them a little air before leaving out.

Steve

I found similar results at the track and the last few AX I did.
I have been running Hankook Ventus V12 evo2's. They are great street tires, love them for canyon carving, but when they hot at the track or AX, they get really greasy and slippery. I found I was dropping PSI a lot. It would help.
At higher temps and then pressure, the tire does not give you the maximum contact patch, hence poorer performance

I just got some 17" wheel for track and AX and am planning on putting RS-3's on them. They came with brand new Sumitomo HTR ZIII's and I will run with them for a but until they are spent.

Tire pressure is really important for traction and a little change can make a big difference. Porsche builds in lots of understeer as it is "safer" for many drivers