Superstar Racing Experience Adds Michael Waltrip to Impressive Driver Lineup Six-race summer SRX short track series to include current and former racing greats from NASCAR, IndyCar, sports cars. Cliff HawkinsGetty Images The Series is set to run over six Saturday nights this summer and will be televised by CBS. Drivers will race in identically prepared cars on both paved and dirt tracks. Michael Waltrip is returning to the racetrack as the latest star from NASCAR, IndyCar and the TransAm Series to commit to the Superstar Racing Experience. The SRX is a six-race short track racing series styled after the old International Race of Champions (IROC) series. It will feature drivers, current and past, from different racing disciplines racing in identically prepared cars for Saturday night races this summer that will be broadcast by CBS. Races will test the drivers on both pavement and dirt racing surfaces.