Originally Posted by CalBearz24

I think that statement is backwards, assuming you're talking about stock vs a wheel with a bigger diameter. The larger overall diameter will lead to your speedo reading slower than your actual speed. To move the same distance, a wheel with larger diameter has to rotate less than a wheel with a smaller diameter. Try that tire calculator that I linked to. My new rims with 215/45/17 tires are 24.6 inches in diameter vs 24.2 inches for my stock 195/60/15. My new tire results in a reading that is 1.7% too slow, so my speedo will read 60 when I'm really going 61. If you're talking stock vs smaller diameter, pretend I didn't say anything.