For a street car i like to keep the same size on the front and back. 245's seem to fit really well. I think the rule of thumb for the best handling is that you want you tire to be 1" wider than your rim. No more, No less. That would mean that on a 7.5 inch pony...the tire should be no wider than a 215!!! But we all know that looks like poop. I think a 245 are going to be a little baloony and possibly a little washy in the corners...but they will look good!