[tnoice]

I autocross my 986S in a "few" autocrosses each year, so I can't speak for the base Boxster, however you must be careful on what modifications you do because it could bump you into a higher class, where you find yourself less than competitive. SCCA is pretty strict about their stock classes.

The best modification I made that made the car a lot better to flog around the course was new tires. I went with the RE11's. They are amazing.

Have fun autocrossing!