1971-’72 PONTIAC TRANS AM
ENGINE
According to The Definitive Firebird & Trans Am Guide 1970½-1981, by Rocky Rotella, for 1972 emissions the 455 H.O. Quadrajet flowed less than the ’71. The intake was revised for an updated heat crossover and the temp sending unit moved to the cylinder head. Among 7F6 head changes were minor port revisions, induction hardening the exhaust valve seat area, and the use of tapered-seat spark plugs. The Unitized Ignition eliminated breaker points and had the coil mounted — and the wires captured — in its cap. Initially standard in 1972, it was then required at extra-cost, and finally, optional.
TRANSMISSION AND AXLE
The heavy-duty M22 close-ratio four-speed and an 11-inch clutch were standard, or the Turbo Hydra-Matic 400 three-speed automatic could be specified at no additional cost. When the optional console wasn’t ordered, the automatic was column-shifted. Though 1970 T/As used a 12-bolt rear axle, beginning in 1971, a 10-bolt axle with an 8.5-inch ring gear was employed.
