Tire pressure
Melting Slicks
Joined: Jun 2007
Posts: 2,263
Likes: 0
From: Paducah Kentucky
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
Interesting to see some of the variations that some of us use.
Don't forget that the 30 psi cold is a compromise figure but one that GM thinks should work for most tires on the market. It can only ever be a compromise because of variations on tire design. Think of just the differences between run flats and non run flats. The RFs have a stiff sidewall and the non RFs relatively soft.
The ideal pressure puts the maximum tread on the road. Too hard and the tread pattern bows outwards (convex) putting the center of the tread more in contact. Too little pressure means the tread bows inwards (concave) leaving the shoulders of the tire in contact but the center less so.
What you need is a figure that works for you giving best grip and even wear.
I run Michelin AS ZPs and generally run them a few psi light. Some who run them harder (in psi) have complained of premature wear in the center which makes sense.
In any event, the figure is going to be somewhere close to the recommended 30psi cold. Inflating to 40+ psi will lead to a hard, jumpy ride and stress on the tire.
Just my 0.02c
Don't forget that the 30 psi cold is a compromise figure but one that GM thinks should work for most tires on the market. It can only ever be a compromise because of variations on tire design. Think of just the differences between run flats and non run flats. The RFs have a stiff sidewall and the non RFs relatively soft.
The ideal pressure puts the maximum tread on the road. Too hard and the tread pattern bows outwards (convex) putting the center of the tread more in contact. Too little pressure means the tread bows inwards (concave) leaving the shoulders of the tire in contact but the center less so.
What you need is a figure that works for you giving best grip and even wear.
I run Michelin AS ZPs and generally run them a few psi light. Some who run them harder (in psi) have complained of premature wear in the center which makes sense.
In any event, the figure is going to be somewhere close to the recommended 30psi cold. Inflating to 40+ psi will lead to a hard, jumpy ride and stress on the tire.
Just my 0.02c
