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      11-16-2011, 08:35 PM   #19
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Drives: P-TurboS. E93M3/335i/Z435i/M5
Join Date: Jun 2009
Location: The Valley, SoCal

iTrader: (298)

Originally Posted by dbarnes View Post
If you've checked "hot" tire pressures and temps then yes you could potentially start with the same "cold" F and R pressures. There are other variables like F/R spring rate, sway bar stiffness/setting, cross weights, tires staggered/unstaggered, etc. that come into play.

By the end of a session are your lap times remaining consistent or dropping off? Is the balance of the car changing? Are the tires getting greasy? If things feel great and lap times aren't dropping off then you have good "cold" pressures.

Also, make sure to adjust your "cold" temps for changes in ambient temp - people forget this a lot and don't bleed off pressure from the morning to afternoon and then can't figure out why their car is handling differently!
I've had session where it's pretty greasy.... but this was when i ran stock psi (35)

once i dropped them to 31/32, things got significantly better.

Lap times for me are a strange thing... I tend to have my off days and on days. I have had better lap times in 100+ heat than I have in cooler days, and vice versa...
So I can't say if they improved due to tire pressure or not

31/32 cold goes up to about 40 hot on hot days, 38-39 on cooler days

35 cold went way past 40...X.x.