Two that came to mind for me were Kent McCord of the TV series Adam-12, who raced Volkswagon Rabbits, and NFL star Walter Payton. who raced in Trans-Am. http://articles.latimes.com/1999/nov/02/sports/sp-28997 http://www.youtube.com/watch?v=7YLzecGDk20
I would most definitely put Ayrton Senna high up on this list (^<^).
Adam Carolla? Anyone?
Petty is a driver who’s celebrity has grown beyond his sport, not a celebrity that moonlighted as a driver.