Join Date: May 2003
Location: Brisbane, Queensland, Australi
Ahh actually, if you change the overall diametre, it will affect the speed and mile counter. Smaller profile tyres on the same size rims, as you are doing, will make you accelerate a tiny bit harder, give the tyres less flex, and the car will say you are doing a speed higher than you actually are, and that you have travelled further than you actually have.
Changing wheel size will NOT effect speed or mile counter, so long as the overall diametre of the tyre is kept the same.