i plan on getting 18s for my 01 cav. z24, will i need to recalibrate the speedometer, i read something somewhere about it i think... if i do anyone tell me where to go to learn how?
As long as you compensate for the large diameter wheels with shorter (lower profile) tires, then no, you won't have to recalibrate the speedometer.
Typically when people upsize wheels and tires, the overall diameter of both combined does not change, or changes a minimal amount.
If you visit a tire/wheel website such as
Discount Tire, they have calculators to help you figure out what size tire you need when you purchase larger wheels.
-Ferrite
if u get 18s
get 225/40/18
and there will be no speedo. diff.