From 1951 to 1971, Langhorne Speedway hosted the Langhorne National Open, which became the nation's most prestigious race for Sportsman and Modified cars. Guaranteed starting positions were awarded to the winners (or highest finishers not already qualified) at special Langhorne Qualifier races held at weekly racetracks throughout the Northeast and Southeast. It was common to have over a hundred cars attempt to qualify for the National Open. From 1951 to 1957, the race was sanctioned by NASCAR. In 1961 and 1962, Supermodifieds raced with the Modifieds and Sportsman cars. Dutch Hoag was the most successful driver, winning five times. Hoag was the only driver to win the National Open on both the dirt and pavement surfaces.