The 1968 Pontiac Firebird 350-cid HO V-8 engine, with high-performance camshaft, better exhaust-gas scavenging, and revised carburetion, delivered 320 horsepower, 35 more than its 326-cid predecessor.
A new 400 HO engine with wilder camshaft and free-flowing exhaust shot an impressive 335 horsepower to the three-speed stick, four-speed (standard or close-ratio), or Turbo Hydra-Matic. Even the regular 400 V-8 included a floor-shift, chrome engine parts, and dual-scoop hood.
Pontiac Firebirds and other General Motors products adopted Astro-Ventilation this year. That simply meant vent wings ahead of the door windows were gone -- a modification less popular with the general public than with GM executives. One-piece door glass looked neat, but didn't do much for airflow.
At midyear, a Ram Air II engine appeared, rated at 340 horsepower, considerably less than the GTO's Ram Air V-8. New round-port cylinder heads gave the engine better breathing. The Ram Air II option included such goodies as a high-lift camshaft, forged aluminum pistons, and Arma-steel crankshaft.
Turbo Hydra-Matic or a four-speed was mandatory. Hood scoops were functional with Ram Air induction, which raised both horsepower and the peak of the engine's power curve.
On city streets, said Sports Car Graphic of its Ram Air Firebird, "the occasional hiss from the quadrajet carburetor and the throaty chug from the dual exhausts gave the impression of enormous power."
A Ram-equipped Firebird could dash to 60 mph in 4.8 seconds, and run the quarter-mile in 15. Not that the 400 HO V-8 was a slouch, with a 5.3-second 0-60 time.