I have a few questions about tires and wheels on my R/T RWD.

How wide of a summer or 3 season tire can one run on a stock sized 7.5x18 rim? If I went to a 9x18 rim how wide? At what width do the tires encounter rubbing problems on the steer tires? As long as I keep the 5.5" backspace is rubbing a concern? I want to keep the stock 18" diameter and the 5.31" (or close) sidewall for ride quality (this car will be used for roadtrips and vacation), and I want to avoid suspension and geometry problems (My past experience has been that putting too much rubber on the road can adversely effect the handling). A 270/50 keeps the sidewall and circumference the same as the stock 225/60 and is the next wider size that is an exact match. Is this too wide?

Next, what winter tires have you folks used that were effective on the Magnum? Or should I just use all season radials? This is the heaviest car I've ever owned, and its been a while since I owned a rear wheel drive car. I'm thinking about winter driving and I'm not sure how the Magnum handles in the snow.

Thanks, Birdman