1970 Buick Gran Sport

General Motors pulled the long-standing corporation-wide restrictions on engine displacement in 1970, which allowed its various divisions to explore new powerplants ranging all the way up to the 455 cubic-inch unit. For Buick, this newfound freedom brought forth one of the most formidable machines of the muscle-car era - the Buick Gran Sport Stage 1. The Gran Sport had the 455 cubic-inch engine rated at 350 horsepower and 510 lb-ft of torque, the latter figure achieved at just 2,800 RPM. Except for the Cadillac 472 and 500 CI, this was the highest torque rating of any production car, and it was due to the higher displacement, larger valves in high-flow heads, a performance cam, and standard cold-air induction fed by twin hood scoops. The Stage 1 went a step further with better breathing, larger valves with stronger springs for high-RPM reliability, a new cam, revised porting, and a rejected version of General Motors Rochester Quadrajet 4-barrel carburetor. The Stage 1 was factory rated at 360 horsepower (in reality, it was closer to 400).

The Buick Gran Sport hardtop coupe had a base price of $3,100. They had a textured black grille with hood scoops. On the left-hand side of the grille, front fenders and deck were GS signatures. Inside there were all-vinyl bench seats in black, blue, or sandalwood. An all-vinyl notchback seat was optional, as were individual front bucket seats.

Standard equipment included dual exhausts, a full-flow oil filter, three-speed manual transmission, heavy-duty shocks and springs, and a semi-enclosed cooling system.

The 1970 Buick Gran Sport 455 (GS) was given a new big-block V8 and Hurst-shifted performance transmissions. In the front were functional hood scoops which brought cold air into the V8s intake. Design features included chrome red-filled lower body and wheelhouse molding with five-spoke 14-inch chrome wheels. On the left-hand blacked-out grille were GS 455 emblems, with others being displayed on the front fenders. A GS monogram was placed on the deck lid.

by Daniel Vaughan | Sep 2019