if your overall size (wheel n tyres) stays the same then there would be no diffrence it will only change if the overall size changes. mad example is if overall size is 25" 20 " tyre and 5" rim change that to a 20" rim and a 5" tyre and it stays the same. to gain acc you would need to change to say 20" overall be it 15" rim and 5" tyre or 5" rim and 15" tyre