1971 PONTIAC FIREBIRD CARRIED OVER
The 1971 models were mostly carried over from the all-new 1970 Firebird, which itself had just launched the 2nd-generation. In its second year, the Firebird didn’t change all that much in appearance, just minor trim and detail differences. Going to the 2nd-gen just the year before was such a radical change from the previous 1st-gen cars that now it was time to settle into this new 2nd-gen platform, as it would be with us for 12 model years, an extraordinarily long time period in the car business. This body style would stay with us through the 1981 model year.
1971 PONTIAC FIREBIRD GETS THE 455
The big news for 1971 was the addition of two more engines (actually two versions of the same engine) on top of the existing engine lineup. Through 1970, the biggest engine you could get in a Firebird was the 400ci V8. Now you could get a 455 V8, perhaps the last high performance engine of the Classic Muscle Car Era. The base engine in 1971 continued to be the 350 ci V8. Next up was the 400 V8. And now 2 versions of the 455, one with lower compression and lower performance. The 455 was an undersquare design (long stroke when compared to the bore), so it was really a torque motor, not a high-rpm engine. Unlike other carmakers, Pontiac built all its V8 engines out of the same basic block, changing them internally, through adjusting the bore and stroke, but with identical outside dimensions. So there aren’t any ‘small block’ or ‘big block’ Pontiacs, they’re all the same on the outside. The 455 was new for 1970, made by boring the old 428 out. GM had just lifted its age-old ban which limited midsized cars to no more than 400 cubic inch engines. So now the 455 came to the Firebird and Trans Am lines and would stay until 1976 when smog regs made it impractical to continue. The process had already started as early as 1971 when even the 455 H.O. (High-Output) only made 335hp, where it made 370hp in the 1970 Grand Prix. Wholesale reduction of compression ratios was to blame, done to compensate for the new low-octane/low-lead fuels the government was mandating.