Tire Size For 16x7's

k but i dont have stock tires on my 240sx … the tires i have on my aftermarket wheels (summer) are 205/55/R16 … so i guess i use that number and go from there right … i jus want to have a bit more grip than what i have without worrying of hittin the fender or it being too bulgy … from what i read in this thread so far, 215/55/R16 are my best bet and no more higher than that … or what if i reduce my sidewall height to 50 and i went with 215’s? would that be better or jus even as the other size?