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Tire Pressures

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874 views 5 replies 6 participants last post by  jmf003  
#1 ·
It'll be a while before I need this info, but it's one of those thoughts that just hangs in the back of your mind and zings you regularly. What are the correct tire pressures for the GTM? The GTM uses Corvette rubber(for the most part) but weighs about 2/3rds of a Corvette, and has a different weight distribution. Seems to me if you use Corvette pressures, your tire "patch" will be smaller, and you'll loose traction and handling capabilities. Is there a way to calculate the correct pressures, or is it purely a matter of trial and error? Best regards, Ted
 
#5 ·
Agreed.. depending on the tires sidewall. Hoosiers take more, Kumhos take less but my experience on cars around 2000 -2500 with radials its in the ball park but a bit low, especially for street tires. With the GTM and the weight split, you are going to want proportionally more in the rear in most cases. If I remember correctly, when autocrossing my PS2's liked around 30 in front and 35 ish in rear.

Crash is right though, really the only way to find out is to test. Id start around low 20's, front 25's rear, and bump it 4ish lbs. It will probably get better, then worse. Fine tune back and then start playing with the front and rear split. Keep the rears around 4-5 psi higher than the front till you start fine tuning.

David
 
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