"The 1974 Delaware 500 was a Winston Cup Series (now Nextel Cup) event held at Dover International Speedway on September 15, 1974. Richard Petty won his 10th and final race of his championship year in dominating fashion, leading 491 of the 500 laps in a three-lap victory over Buddy Baker. Stats"@en . . . "The 1974 Delaware 500 was a Winston Cup Series (now Nextel Cup) event held at Dover International Speedway on September 15, 1974. Richard Petty won his 10th and final race of his championship year in dominating fashion, leading 491 of the 500 laps in a three-lap victory over Buddy Baker. Stats"@en . "1974 Delaware 500"@en . .