The mid to late 1960s had been a time of increasing performance for Detroit’s muscle cars. As 1970 approached, so did looming fuel economy standards, reticence among insurers to cover powerful street cars piloted by young drivers, and governmental regulations such as the Clean Air Act, all of which would combine to throw a wet blanket on all the big-muscle fun. 1970 would be the final year of the raw, unadulterated, visceral performance muscle cars. GM decided to go out with a bang, lifting their corporate restriction limiting mid-size passenger cars to 400 cubic inches of displacement. For the Buick GS, this meant 455 cubes of hairy chested Big Block under the hood.
The Buick GS with the 455 put out a claimed 350 horsepower and a startling 510 pound-feet of torque. In the Hot Rod magazine road test, a 1970 Buick GS ran a 14.4-second quarter mile at 96 miles per hour on street tires. The 455 was a thin-walled block, meaning it weighed 150 fewer pounds than Chevy‘s 454 Big Block, and just 25 pounds more than the Small Block 350.
The Buick Skylark on which the GS was based was a near-luxury car with a rather plush ride. To deal with the added power of the 455, the Buick GS was equipped with the F41 Special Suspension package that included a beefier front sway bar, rear sway bar, stiffer springs, firmer shocks, boxed lower rear control arms, and a stiffened frame in the rear.
The 1970 Buick GS received a facelift and a bit of extra length, adding two inches to the overall length while the wheelbase remained the same as the previous year.
Our feature 1970 Buick GS convertible is finished in Regal Black with a white vinyl convertible top over a Sandalwood vinyl interior. It is powered by a 455 cubic-inch Big Block V8 backed by a three-speed Turbo Hydramatic automatic transmission. The GS is equipped with a power convertible top, heater/defroster, woodgrain interior trim, 120 MPH speedometer, power brakes, power steering, and dual exhaust. In-cabin entertainment comes from an aftermarket USB head unit. It appears to have recently had the rear springs replaced, as the rear end has yet to settle.
This attractive 1970 Buick GS will soon cross the Mecum Auctions block at its Dallas, Texas event taking place September 20th through the 23rd.