For those fans of American performance cars, the world came to an end (at least temporarily) after the 1974 model year. The GTO, once the king of muscle cars, had been relegated to a 350 V-8 on a chassis shared with Pontiac’s compact Ventura, and it was conspicuously absent from the model lineup the following year. Furthermore, the special Super Duty 455 V-8, available in Firebirds, was never to return.
Beginning in 1975, catalytic converters were the new norm and necessitated the use of unleaded fuel; 5-mph bumpers were now passe; and computer-controlled engines were in their infancy. The last vestiges of performance were struggling to survive. For Pontiac, whose sales success of the late Fifties to the early Seventies relied on performance, things looked bleak.
Sure, you could still order a big 455 in your new Grand Ville, Bonneville, Catalina, Grand Prix, Le Mans, or Grand Am,
