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Old 10-22-2007, 12:45 PM
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tdatk tdatk is offline
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Quote:
Originally Posted by Toby View Post
Tim,

You need to run much higher pressure. The tires are rolling over too much.

Also cold pressure is not a relevant measure. The difference is huge if it's 40F or 90F ambient temp. You should set your tires' hot temp right after you come in. Street tires should run at least 40psi hot.

(You will notice that as you run harder and heat up you tires more, you will start with lower cold pressure.)

Re: feathering, your tires don't look too bad. All non-slicks (incl. unshaved RA1's) will feather a bit due to the hard braking and cornering.

Toby
Thanks Toby,
I checked the tire pressure on my next to last run (3rd) right after I came in and they were 34 fr and 37R which gave me the most predictable comfort going through the corners although high speed stability/brakeing was less. When I took HPDC, Charlie (my on track instructor) drove my car and when we pitted he checked my contact patch and recomended lowering pressures to achieve more contact as he felt it was too loose.
I'm a little pissed at my tire choice as I feel ,even at my level of understanding of tires, that GYE's on my car were a poor choice. I was running slow by most standards on repeatable lines and they were squalling throughout the event, which means loosing traction. If I tried to push a little harder the rear would try to come around and I'd have to catch it.
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Tim
05 Cayenne TT
03 M3 (sold)
82 911 SC (sold missed)
90 C2 (sold missed)
87 928 S4 (sold)
85.5 9 fofo (sold )
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