Well from a acceleration standpoint they would slow the car down. Take a saucer plate(coffe plateetc.) then take a dinner plate and stand them on their side. Make one full rotation with each plate. Which one went further? Since the dinner plate is larger thus covers more area. So in acceleration(drag racing) a smaller wheel gives the car quicker acceleration. Now on top end the larger wheel(or dinner plate) would be faster. Plus with a smaller rim the tire will have more sidewall. Which will give the tire more of a chance to wrinkle the sidewall(i.e. slicks) If u want a wheel for acceleration go w/ a small wheel. If u want a wheel for more high speed racing then go with the dinner plate uh Im mean larger rim. -Mark