Pontiac Super Duty 421


  • This engine was an expensive limited option in 1962-63 and was offered on Catalina and Gran Prix models
  • Super Duty motors featured a high nickel cast iron block with 4 bolt mains, forged steel rods and crankshaft, Mickey Thompson forged aluminum pistons, and a solid lifter McKeller #10 Camshaft
  • The exhaust manifolds were either cast iron (road) or aluminum (strip) and cast with a split-flow duel outlet design topped with cast iron exhaust “cutouts”
  • It was rated at 405 hp @ 5,600 rpm but was actually closer to 460 hp
  • Drag racing versions came topped with two four-barrel carbs while the NASCAR version came with one large four barrel
  • This 1963 engine is prime example of Pontiac greatness. It contains all the hard to find 421 SD components such as the twin carbs, aluminum intake, big valve “NASCAR” heads, forged crankshaft, duel point distributor, extremely rare balancer, upside-down starter, bell housing, and split flow exhaust manifolds