Tony Stewart loves driving his dirt cars, and nothing, not even the thought of bodily harm, is going to change his mind. It’s nothing new in NASCAR to see top drivers moonlighting on off nights at dirt bullrings, but Stewart is more dedicated than most. Until breaking both bones in his right lower leg in an accident at Southern Iowa Speedway—a dirt track—in early August Stewart had planned on racing 70 times on the dirt in 2013.