[944boy]

Well I am used to running the same size tire all the way around. You might want a little more on a wider tire (rear) and less on the front. I would at least start out the same. If its pushing you can raise the rear a little or lower the front a hair or opposite for oversteer. Whenever you make adjustments, do it in one or two pound increments. Also its good to make note of the outside temp and pressures in a logbook. That way you get a feel for what is working and have to do less guessing in the future. The best way to tell what the best pressure is; is with a pyrometer, but correct readings are an art and that's only truly needed if your really serious and competitive. For most of us, 'feel' of the car, how much the tire is rolling over, and a working knowledge of how the tire behaves can get you quite far.