The United States Auto Club (USAC) sanctions the Weld Racing Silver Crown Series. This 13 race series is run on paved and dirt tracks ranging from 1/2 mile to 1 mile in length. Silver Crown cars sport a 355 cu in V-8 that produces 700 to 730 hp , and pushes them to over 170 mph on the straights. The top echelon of USAC racing, the Silver Crown series races are 100 miles or 100 laps depending on the track. The USAC Silver Crown has produced many legendary current and former drivers from Jeff Gordon, Tony Stewart, and Kasey Kahne to A.J. Foyt, Mario Andretti, and Al Unser, Sr.