Originally posted by Spec R
Stock should be a 15 inch rim, with a 195/55/15 tire size.
Stability also depends on a whole slew of different factors, but in your case and the case of your friends car, the actual tire plays a big role. When you get bigger rims, you also get lower profile aka "series", to attempt to keep the overall diameter of the wheel and tire down as close to stock as well as fender clearance to prevent any rubbing. the middle number (the 55) of 195/55/15 is the percentage of width (the 195mm in this case) that the height of the sidewall of the tire is.
if you were to get 17's, tire size could either be 215 or 205/40/17. A 45 series could and most likely would cause u to rub. But then again the lower profile you go, the more harsh the ride can be. I can go on and on, but keep posting your questions so i can answer them the best i can one by one.
No I understand totaly. I'm definetly looking for a 15" rim now. That seems to be my best bet.