dfink, just a note, putting larger tires on your car is not going to increase the size of the contact patch, only change it's shape. You'll probably actually get better results (handling/traction) by getting the best/stickiest tire not the largest. If you keep the sidewall the same approx height you'll probably get better handling characteristics from a smaller tire on the same rim, ie. on a 16x7 you can fit a 245 45 16 and a 225 50 16, assuming the same tire just different sizes the 225 50 will handle better because of less flex.

If you are only or primarily interested in looks then the 245 will be fine.

For the size choice I am just using the tire specs for the A3s04 which for that particular tire has an 8" listed for the 245-50-15 and 7" for the 225-55-15. They give a small range with a preferred rim width. I am trying to stay in the stock class for scca soloII and have to use stock wheels. The rule book does not list any tire restrictions other than DOT and must fit under the stock fender. I assume that since these are the recommended tires for that size wheel the tires will not have inappropriate buldge. To go smaller I would have to goto 225-45-15 and 205-50-15 squatty little buggers at only 22.8 inches tall. Nearly three inches shorter than stock. Would give me better low end and could possibly make better use 2nd gear. Hoosier is the only place I can find that still makes any 15" competition tires. Lots of other choices if not stuck to the stock wheels. hoosier

That is good info. I guess I am in it for looks 1st, street (the streets of San Diego) performance a close second. No tracking for the cab.

As long as I can pass the occasional ricer, then I am content. (Until the next stop light).