Originally Posted By: Olas
Depends how the car handles with that particular rubber on.
Higher pressures in the rear = prone to oversteer
Higher pressures in the front = prone to understeer
I'll tweak the pressures over the first week of having the new rubber to find a pressure I'm happy with.
Higher pressure means (unless excessive enough to alter the contact patch) a LOWER slip angle which on the rear would keep the rear from moving OUT in cornering, thus causing UNDERSTEER. Higher pressure in the FRONT causes the fronts (with the same caveat) to run at a LOWER slip angle and thus cause the steering to become MORE responsive and closer to neutral, especially with Front WD where the fronts do so much of the work. IF you have been doing the opposite you must have some strange handling vehicles. The goal is neutral handling where both ends operate at the same slip angle. The safety Nazis, of course, want cars to understeer like pigs because it's "safer" than being tail happy, as they say. The sidewall pressure listing is for maximum load and speed use, the car maker knows a whole lot more about the proper pressure for the vehicle that what's on the sidewall of a tire which could be fitted to many different products with different drives and weights. I usually adjust UP from the "one passenger" listing on the sticker, but seldom by more than a few pounds, given the sorry state of our roads. 45 pounds in a Camry and you'll be buying a lot of suspension pieces over time.