Uncover the shocking truth behind Pontiac Banned 421 Super Duty Engine! in this must watch video! Learn about the history and controversy surrounding this legendary engine.
this is a tale of engineering brilliance, corporate secrecy, and a powerplant so soo Powerful NASCAR had to "outlawed it" to keep the competition fair.
history
The 421 Super Duty was a high-performance V8 engine produced by Pontiac in the early 1960s. It was designed for racing and high-performance street use, featuring robust internals, high-flow cylinder heads, and a focus on durability and power. The engine was a favorite among drag racers and NASCAR competitors due to its impressive output and reliability.
421 CID Super Duty 1961-1966 built
Key Specifications
Super Duty 421 CID V-8 option in Catalina two-door only: Overhead valves. Cast iron block. Five main bearings.
Displacement: 421 CID.
Bore and stroke: 4.09375 x 4.00″.
Compression ratio: 11.00:1.
Horsepower: 405 @ 5600 RPM.
Torque: 425 @ 4400 RPM.
Valve lifters: Mechanical. 1.65:1-ratio rocker arms.
Camshaft timing:
Carburetors: Two Carter AFB 3433S (Front) 435S (Rear).
NOTE 1: various camshafts were used in this engine.
NOTE 2: The SD engines were discontinued after January 1963.
https://over-drive-magazine.com/2022/09/30/1963-pontiac-fact-sheet/
Introduced in 1961 as a dealer installed Super Duty option (to bona fide racers), the 421 cu. in. V8 was the 389 design bored to 4.09375″ and stroked to 4.00″ for 421.2 cu. in. Its primary difference was larger, 3.25″ main journals and 4-bolt 2-4 main journal caps. Unlike previous displacement increases of Pontiac V8 engine, it did not replace the 389. The Super Duty versions were extensively used in NASCAR stock car racing and drag racing competition.
The 421 also marked the end of the option for a forged steel crankshaft, which was replaced by an “Armasteel” cast nodular iron crankshaft. This became the standard crankshaft of the entire Pontiac V-8 line until ’67. “Armasteel” was no more than a fancy name for a hardened cast iron unit. In 1967, with advent of the 428, Pontiac went to the common “Nodular Cast Iron” name for this crankshaft, which they used until 1975.
The blocks were cast with the provision for 4-bolt mains at positions 2-4 and all large journal engines have this provision, though many “HO” versions are not fitted with 4-bolt caps.
AMERICAN Car History, Season 1
The Shocking Truth behind Pontiac Banned 421 Super Duty Engine!
https://youtu.be/U9QEeL3_N68
The Shocking Truth behind Chevrolet Banned 396 Big Block Engine!
https://youtu.be/StrfpfUWcRM
The Shocking Truth behind FORDs Banned 427 SOHC Cammer Engine!
https://youtu.be/Ywaj6g5pG8U
The Shocking Truth Behind Chevrolet's Banned Mystery Motor
https://youtu.be/KtvxnPvycm4
The most FORGOTTEN engine of 1960s Ford 351 Cleveland
https://youtu.be/JyI2QYF2IQA
The Shocking Truth behind Ford’s Banned BOSS 429 Engine!
https://youtu.be/tFsHhRMBOOU
BUILT TO DESTROY SHELBY 1966 Chevrolet Corvair Yenko Stinger
https://youtu.be/JaBQRk18CTA
FASTER THAN A HELLCAT? 1964 Ford Fairlane Thunderbolt
https://youtu.be/os43VNt_xgo
Ford Dreaded 1963 Chevy's 427 Beast
https://youtu.be/Bj-jijXPQH8
CRAZIEST Corvette Ever Made! 1967 L88 Corvette
https://youtu.be/v-Fjqdq0_Uw
RAREST 1981 YENKO CAMARO Z28 TURBO
https://youtu.be/9hhW6D6XX2k
NASCAR
The "Banned" Myth
The idea that the 421 Super Duty was "banned" stems from its dominance in racing during its time. In the early 1960s, NASCAR and other racing organizations had strict rules about engine modifications and homologation requirements (meaning engines had to be available in production cars to be eligible for racing). The 421 Super Duty was so advanced and purpose-built for racing that it raised concerns among competitors and officials.
In 1963, NASCAR introduced new rules that effectively limited the competitiveness of the 421 Super Duty. These rules included restrictions on engine displacement and modifications, which made it difficult for the 421 to compete without significant changes. While the engine wasn't explicitly "banned," the new regulations made it less viable in NASCAR competition.
Similarly, in drag racing, the 421 Super Duty's dominance led to class restrictions and rule changes to level the playing field. This has been misinterpreted over time as an outright ban, but it was more about maintaining competitive balance.
The Legacy of the 421 Super Duty
Best Community Comments , Thank You
@scottdevaney3928
What did the 421 in Smoky Unix did they change the main bearings from the side of the word to a bigger one which he was said would make it more unstable and slower and he walked away from the program they went from a smaller Journal bearing size to a larger one 10 seconds unless they had a big nitrous bottle of supercharger turbocharger in a f**** NASA rocket on it
Corections
Join this channel to get access to perks:
https://www.youtube.com/channel/UC1LFwBRy9-ENQ5I20vxw08g/join