I have a 2008 mini cooper S convertible with the JCW engine package. It has the normal 205/45/17 tires. They simply don't have enough rubber on the road for the engine's power.... does anyone know how wide I can go before I start getting into trouble with the tires rubbing the suspension or causing turning problems? I am thinking I want to go to 235/40/17 which have almost the identical diameter / sidewall but are an inch wider...anyone have any experience?