Much to the surprise of competitors, media, and fans, Marlboro Team Penske arrived at the Indianapolis Motor Speedway with a brand new, secretly-built 209 cid Mercedes-Benz pushrod engine, which was capable of a reported 1000 horsepower. Despite reliability issues with the engine and handling difficulties with the chassis, the three-car Penske team (Unser, Emerson Fittipaldi and Paul Tracy) dominated most of the month, and nearly the entire race. This engine used a provision in the rules intended for stock block pushrod engines such as the V-6 Buick engines that allowed an extra 650 cm³ and 10 inches (4.9 psi/33.8 kPa) of boost. This extra power (1,024 horsepower, which was up a 150-200 hp advantage over the conventional V-8s.) allowed the Penskes to run significantly faster, giving them the pole and outside front row on the grid for the 78th Indianapolis 500. Al Unser, Jr. and Emerson Fittipaldi dominated the race, eventually lapping the field with 16 laps to go in the 200 lap race when Emerson made contact with a wall coming out of Turn 4, giving Al Unser, Jr. the lead and win. The only other driver who finished on the lead lap was rookie Jacques Villeneuve.