When I bought my car, the speedometer was fast by 10mph. I have changed the rim and tire size from stock, and thats what everyone I haved talked to think it is. But, the speedometer is fast 10mph exactly at 35, 50, and at 70... if it were the rims fault, wouldn't it be different at different speeds? The owner before me installed white faced guages, could he haved bumped the needle during the install? I talked to Jeff at Jay Marks, and he said he has never heard of anything like that, and that I would probably have to live with it. I am pretty much used to it by now, but would really like an accurate speedometer... any suggestions would help...