when switching over to 18" wheels, assuming that you had the stock 17"s, how much does the body go up, if at all?

 

depending on the tire size, could be a little and could be alot. Mine went up a bit, but hotchkis springs took care of that.

stock 17s

18s

 

Stay with a 225/40R18 tire when you upgrade and you will be fine.

 

if you get the proper tires to fit the new 18s, it won't make noticeable difference in height. if you are going from stock 17s (215/45/17) then you would want to get 225/40/18 tires for the new 18s to keep the same overall diameter of the wheel. i personally would get 235/35/18 as its even closer to the stock tire size so your speedo and overall diameter wont be so far off as the 225/40/18s. however make sure you can fit them without rubbing, 235's required at least an 8 inch wide rim.

http://www.discounttiredirect.com/di...foTireMath.jsp

 

The body will sit a little bit higher. I have two friends with the same springs, I have the 18's and they have the 17's. They sit a bit lower than me.