I'm about to buy new 17" tires for my 2003 coupe. Following some of the threads, I see that you can neutralize understeer by modifying the OEM tire sizes. Could you tire experts tell me how I would change the standard sizes (225/50VR17/235/50VR17) to make that happen? Thanks.

 

Well it kinda depends on what your suspension setup is right now. If you are stock then you can neutralize understeer just by ditching the stock staggered setup and going with the same size wheel and tires all the way around. SportCompactCar was able to pull 1.02 lateral G's on the skidpad on a stock 350Z doing 4 modifications, one of which included getting new wheels and tires all the same size front and back.

http://www.sportcompactcarweb.com/pr.../0404scc_350z/

 

could mess up VDC...

Grippier tires will do, but you should consider getting a swaybar set and
stiffen up the rear a little more than the front.