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thstone · 09-23-2012, 06:12 AM

Everything is a tradeoff.

Depends on the make/model of your tire and what you're trying to acheive. There is no single "right answer" for tire pressures and many people have different preferences in terms of ride quality, balance (understeer vs oversteer), tire wear, and several other key handling characteristics that can be somewhat altered by varying the tire pressure.

A gross example is the difference between the Nitto NT-01 and Toyo R888, both R-compound racing tires. The Nitto's typically run best at 36-38 psi hot (all four corners) but the Toyo's, with a stiffer sidewall, run best around 30psi (all around). Running either tire at 5 psi more than these values results in a greasy, loose feeling, and loss of ultimate grip. Running at 5psi less than these values usually results in rolling the tire too far over in hard corners. Within this range, there is a lot of room for variation and preference.

Read the posts and then try making some minor changes to tire pressures to see if you feel any difference or improvement in the direction that you want to go. If so, then move a little more. Eventually, you'll reach a point of diminishing returns or where a negative tradeoff starts to become apparrent.

09-23-2012, 06:12 AM	#3
thstone Certified Boxster Addict Join Date: Nov 2010 Location: Los Angeles Posts: 7,669	Everything is a tradeoff. Depends on the make/model of your tire and what you're trying to acheive. There is no single "right answer" for tire pressures and many people have different preferences in terms of ride quality, balance (understeer vs oversteer), tire wear, and several other key handling characteristics that can be somewhat altered by varying the tire pressure. A gross example is the difference between the Nitto NT-01 and Toyo R888, both R-compound racing tires. The Nitto's typically run best at 36-38 psi hot (all four corners) but the Toyo's, with a stiffer sidewall, run best around 30psi (all around). Running either tire at 5 psi more than these values results in a greasy, loose feeling, and loss of ultimate grip. Running at 5psi less than these values usually results in rolling the tire too far over in hard corners. Within this range, there is a lot of room for variation and preference. Read the posts and then try making some minor changes to tire pressures to see if you feel any difference or improvement in the direction that you want to go. If so, then move a little more. Eventually, you'll reach a point of diminishing returns or where a negative tradeoff starts to become apparrent. __________________ 1999 996 C2 - sold - bought back - sold for more 1997 Spec Boxster BSR #254 1979 911 SC POC Licensed DE/TT Instructor Last edited by thstone; 09-23-2012 at 06:16 AM.