[rattlsnak]

If you want to do this correctly, you must use a tire temp guage. You want equal temps on the inside, middle and outside edges of the tires. If the temps are equal, but too low, than take some air out,etc. Once this is accomplished-by varying tire pressures- then deal with why the car is pushing or sliding by adjusting your suspension, and then repeating the tire temps again. It is not wise just to add/remove air on certain tires to correct for car setup problems.