put 20" axis mods on my Z. i always turn off the vdc because im not sure if the new tires will mess with it. will these aftermarket rims/tires affect vdc readings?

 

It is the tires that make the difference--not the rims. What tires are you running?

Chances are, if you are running a wider rear tire than the front, with the same series (i.e. 35) you will be fine. You just need to have the rear tires taller than the fronts as the VDC was programmed to read wheels speed based upon the stock staggering.

 

i think the front is 35 series and the back is 30 series. 245/20 in front and 275/20 in back