by NASTY » Fri Dec 20, 2002 4:15 pm
215/50's is the closest to stock diameter
as for an equaion, i dont see why there wouldnt be an easy one
for example using the stock size (205/60R16)
multiply the aspect ratio (2nd #) by tire width (1st #), divide by 100 (because aspect ratio is a percentage)
take that number, multiply it by 2 (top and bottom of tire), and then add the rim diameter (16"X25=400mm)
sooo the overall stock diameter (rim and tire) would be 646mm=25.84" (sounds kinda big, did i screw up somewhere?)
anyways, do that same thing with an aftermarket wheel/tire combo, and calculate one as a % of the other, thats how much it will be off
'01 SLE V6