AJ’s “Badass Friday” Car of the Day: 1970 Buick Gran Sport 455 Stage-1 Coupe

AJ’s “Badass Friday” Car of the Day: 1970 Buick Gran Sport 455 Stage-1 Coupe

Car: Buick Gran Sport 455 Stage-1 Coupe

Year: 1970

What makes it special: The Gran Sport name has been used on several high-performance cars built by Buick since 1965. In the GM brands hierarchy, Buick was surpassed in luxury and comfort appointments only by Cadillac, which did not produce performance models. As a result, the Buick GS series were the most opulently equipped GM sport models of their era.  

What made it famous: The 400 was replaced for 1970 with the Buick 455 cu in V8 engine, used in the GS 455. The base model was rated at 350 bhp and 510 lb⋅ft at 2800 rpm of torque. The Stage 1 engine option used cylinder heads that, while using raw castings of the same pattern as all of the other Buick 455’s sharing the same model year, were machined differently in order to accept larger valves, and to produce smaller compression chambers for increased static compression ratio. The option also included a more aggressive camshaft, a specially tuned 4-barrel Quadrajet carburetor, more aggressive ignition timing, 5/8 inch oil pickup tube and a higher numerical final drive, and was available with either Turbo-Hydramatic 400 3-speed automatic transmission, or a Muncie M-22 4-speed manual transmission. Buick perfected performance mechanically as well as aesthetically. At the front, you had a silver-trimmed grille with a bold GS Stage-I emblem and a scooped hood, and at the back, you had Buick script between clear taillights set in a chrome bumper with a GS emblem. A rear deck and front chin spoiler was available.

Why I would want one: This is the ultimate Buick performance model, and the last performance models until the Buick Grand National made its debut in the mid-80’s.

Fun fact: There was also a rare “Stage 2” option produced. This was a dealer-installed package known as a “dealer option.” first offered in 1969. It included a cam, headers, intake manifold, high compression forged pistons, hollow pushrods, and some calibration changes to the ignition and carburetor .