Nitto NT555
 

Just purchased some Nittos NT555 for my car. I have the non sport model and still roll with the facotry rims. I changed the size on the Tires to 275/40 for the rear and 245/45 for the front. I know peple run larger sizes on there sport rims but has anyone done this with the 18's? Can i go bigger and does anyone has experience with these nittos?