When everyone was in panic mode and scrambling to meet the emission standards by deadline, Pontiac had the audacity to also produce the very potent, tougher to smog SD-455. It was delayed during certification & reworked. That spelled the end of the idea of offering the Super Duty in any A-body Pontiacs. I had heard from one source that after getting all the special unique parts cast or forged, a lot of parts sort of left the plant in lunch boxes. The article stated on the other hand that the delay in getting the Super Duty to market and the knowledge of the special parts caused a bit of a parts counter run on the stockpile of parts from which to make the engines. Both seem plausible.
I like the way they explain why the Formulas with SD power got the shaker rather than the twin scooped hood, basically it was expedient.
Oldsmobile was also seriously toying with the idea of an emissions-legal production 1974 W30 455. They had the engineering toy at the proving grounds in the summer of '73. Seeing the EPA delays that Pontiac had, plus the Arab oil embargo of October 1973 a few weeks after 1974 introduction, deflated any hopes of getting it to market. The market for 8 to 10 mpg supercars died right there, after being wounded first by insurance then by emissions.
Chevy had toyed with the idea of an LT-1 -ized 400 around 1972 with an eye towards emissions and the impending demise of the 402 BBC. It would have been very potent in a Camaro or Nova as they prepared to enter the malaise era.
Very cool story on those cars, I had a '76 T/A 400/400 for 7-8 yrs but the EX ended up with it
EX says it all. My brother's friend bought new a gold '78 Trans Am special edition with the Fisher T-tops, 15x8 snowflakes, T/A 6.6 & 4-speed, 3.23 Safe-T-Track and seemingly all the toys. His EX got the car, which she drove year round, didn't really know how to drive, and neglected through ignorance.