What engine displacement did the 1970 Buick GSX Stage 1 feature?

The 1970 Buick GSX Stage 1 featured a 455-cubic-inch V8. Buick based the GSX on its Gran Sport and GS 455, then added distinctive styling, suspension upgrades, and the optional Stage 1 engine package for extra performance.

The Buick 455 was notable for producing enormous torque while weighing less than several rival big-block engines. Stage 1 equipment included revised cylinder heads, larger valves, a more aggressive camshaft, a specially calibrated Rochester Quadrajet carburetor, improved ignition tuning, and a higher numerical final-drive ratio. Buyers could pair it with an automatic or four-speed manual transmission.

A common mix-up is confusing the Buick 455 with the Chevrolet 454. Both were big-block V8s from the same muscle-car era, but they were different engines from different GM divisions. The GSX Stage 1 used Buick’s 455, not Chevrolet’s 454 or Buick’s earlier 400.

The 1970 GSX was exceptionally rare: Buick built 678 examples, including 400 equipped with Stage 1. That combination of rarity, torque, and dramatic graphics helped make the GSX one of Buick’s most collectible muscle cars.