Doc Hudson had won three Piston Cups before his racing career ended in Pixar’s Cars.
Doc’s past is a key part of the film’s character history. As the Fabulous Hudson Hornet, he was a highly successful racer, but a crash and the racing world’s reaction to his recovery caused him to leave the sport.
When Lightning McQueen meets Doc, he initially sees only an irritable small-town doctor. The discovery of Doc’s three Piston Cup victories changes McQueen’s understanding of him and reveals that the older car was once a celebrated champion.
The Piston Cup is a fictional racing trophy in the Cars universe. It is not the same as a real-world NASCAR championship, although Doc’s Hudson Hornet history draws inspiration from stock-car racing.