Doc Hudson had won three Piston Cups before meeting Lightning McQueen in Pixar's Cars.
Doc's racing history is revealed after Lightning discovers that the town's quiet judge was once the Fabulous Hudson Hornet. Doc won the Piston Cup three times, in 1951, 1952, and 1953, before a serious crash ended his racing career.
His career reflects the real-world Hudson Hornet, a car associated with early stock-car racing success. In the film, Doc becomes bitter because the racing world moved on after his injury, leaving him with painful memories of being replaced.
Lightning initially dismisses Doc, but Doc eventually trains him and helps him understand racing as more than personal glory. The three victories are separate from Lightning's later Piston Cup accomplishments.