Breaking in shaved RA1's
05-02-2007 | 03:56 PM
#16
Race Director
Joined: Aug 2002
Posts: 17,643
Likes: 8
From: Phoenix, Az
You read that wrong.
Start 34/36 cold when new
After that start 34/32 cold to achieve 40 psi hot.
Personally I run 32 cold to achieve 38-39 hot and I have never started with different pressure new or used.
Start 34/36 cold when new
After that start 34/32 cold to achieve 40 psi hot.
Personally I run 32 cold to achieve 38-39 hot and I have never started with different pressure new or used.
05-02-2007 | 03:58 PM
#17
Rennlist Member
Joined: Aug 2006
Posts: 41,905
Likes: 1,748
From: All Ate Up With Motor
You guys need probe pyrometers to ascertain where your starting pressures should be. I have different starting pressures on different corners for different tracks/configurations, all based on using a pyrometer.
05-02-2007 | 04:11 PM
#18
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Joined: Oct 2005
Posts: 4,447
Likes: 37
From: On Rennlist, apparently
Originally Posted by 171mph
34 at front when hot? interesting. I have a cayman s and run 38 front/back when hot (pretty evenly balanced rear/front). do you find 34 at front causing understeer at all?
05-02-2007 | 10:08 PM
#20
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Joined: Jan 2005
Posts: 12,346
Likes: 4
From: New Jersey
Cold start pressures required to achieve a specific hot pressure varies by the car and the suspension set-up in my experience. As Dave said, a pyrometer is required, and a durometer is good to have also.