The correct size should be 215/45/17 or 225/40/17 It's ok to go with 215/50/17 you'll just have a little more meat on your tires. But if you go with that size, you will have to drop your car around 2 inches cause your car will be pretty high. Look at the pic in my sig. I dropped my car 1 1/2 in in teh front and 1 1/2 in the rear
Good luck