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History Of The Pontiac Firebird

1973 - Being #1

   Despite the gloom of a disastrous strike at the Norwood, Ohio assembly plant, the oil shock of 1973 and a looming auto insurance crisis Pontiac forged ahead with a rather daring plan to introduce a new version of the 455, prefixed the 'Super Duty," for the 1973 Firebird, at a time when big-displacement performance engines were becoming a rare sight in the showroom. The Firebird V-8's displacement to 455 cu in. Two 455s were planned for the Formula and Trans Am, and both were rated in gross and net horsepower as the SAE net output formula gradually replaced the unladed gross ratings that GM used previously.  The  “Cooking” 455 was rated at 325-gross/255 net bhp, while the 455 HO was good for an additional 60 bhp net!


Designed for the new realities of low-octane fuel and emission controls, the engine was announced at 310 bhp, but was down rated to 290 when it entered production. That was still power enough to get so-equipped Trans Am’s to 60 mph in less than 5.5 seconds. And, they would likely continue to perform for years to come, thanks to the SD's robust construction, which included 4-bolt main bearings with a provision for dry-sump lubrication just in case someone wanted to take it racing, of course. Other tasty tidbits ranged from forged pistons and connecting rods to large-port heads and a more generous Quadra jet carburetor. The engine helped Pontiac retain the Firebird's position at the upper end of the pony car performance spectrum.  



 CONTINUE READING - 1974 What Oil Embargo? 


Photo's Courtesy: The Premier Firebird Trans-Am Gallery.

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