The 421 actually made its racetrack debut a few weeks earlier, when Hayden Proffitt drove a 421-equipped Pontiac to a win at the Pomona Valley Timing Association’s Top Stock championship. The Super Duty 421 landed under the broad hoods of the Catalina and Ventura in 1962, with a forged steel crankshaft and connecting rods and forged aluminum pistons. It shared its cylinder heads with the 389 Super Duty V8, and was topped with two Carter four-barrel carburetors. The 421 was officially rated at 405 horsepower, but a Motor Trend road test found the engine’s output to be around 60hp more than that. In a nod to numerical symmetry, Pontiac only built 421 Catalinas with the 421 Super Duty engine in 1962, but the brand dominated the NASCAR circuit that year.
Glenn “Fireball” Roberts won the Daytona 500 with a Pontiac 421. Joe Weatherly won nine Grand National Series races and scored 39 top five finishes in 52 runs en route to a championship win in 1962. For 1963, Pontiac boosted the compression ratio from 11.0:1 to 12.0:1, increasing the redline to 6,400 rpm.
The Catalina was also lightened by using aluminum in some front-end components and drilling holes in the frame. The 1963 Catalina with the Super Duty 421 could go from 0-60 mph in 5.3 seconds, a full 7/10 of a second faster than that year’s Chevy Corvette.
