255/50-16 is the widest "recommended" tire for a 16x7 inch wheel like ours but if you use that, your speedometer will be almost 5% off and you may get rubbing because the overall cicumference is bigger. but if you go to 45 series tires, the widest your supposed to run is 215. so obviously there is quite a buldge with even the stock size of 225/50. ive always thought the 225s look too wide on the sawblades.
if your car is purely drag, then 245s or 255s might be ok, but if you want to turn with any sort of precision i would suggest sticking with the stock size.