@Admin posted:The ideal gas law says the change in pressure for a given change in temperature will be the same regardless of the size of the tire or the initial pressure.
There may be a difference between two different tires in the way their calibration constants change as the temperature changes, but it is not due to a difference in how much the pressure changes between the two.
Big wide tires tend to have thicker tread(and often knobby tread), and the material properties of most rubbers change significantly with temperature, so that can change the calibration constant. But a big wide tire with thin smooth tread will result in a calibration constant that probably won't be more sensitive to temperature change than a small narrow tire with thin smooth tread.
I agree with you, that with the same starting pressure the pressure change would be the same for the same change in temperature (PV=nRT). But, do you think that the diameter of the tire will change more on a fat tire than an thin one, given the same change in pressure?