Should you run 32psi all around even if you have larger rims (such as 17's)? I've been wondering this for awhile now because it seems to me a smaller tire would require more psi. Also, when should I measure the pressure, after driving or while they are cold? Mine vary, on cold mornings they are 28psi and they range up to 32psi after a long highway drive.
Thank you,
Alex

 

I'm a little confused by your question since running a larger rim usually means a slightly wider tire. Yes, the sidewall is shorter, but a correctly setup wheel will have the same rolling diameter as stock. What do you mean by "smaller tire"?

You should adjust tire pressure when the tires are "cold". Pressure changes approximately 1 psi for every 10 degrees F of temperature change. Thus, the increase in pressure after driving (the tire is heated up) is normal and accounted for in the pressure recommendations of the manufacturer.

If you're running aftermarket wheels, many parameters could have changed in addition to the rim diameter. In general, the tires fitted to such a rim should be only slightly wider and about the same diameter as the OEM tires, so I'd run 34 to 36 psi front and 32 to 34 psi rear depending on whether you want a softer ride (lower) or better feel (higher).

 

Moving to Wheel/Tire forum.