Buick Grand National

Muscle car with a turbo V6 engine

Buick Regal Grand National. Named for the NASCAR Grand National racing series, this car incorporated a 4.1 L V6 with 125 hp or an optional 180 hp turbocharged 3.8 L V6 . There was no Grand National in 1983, but it returned in 1984 wrapped in its familiar all black paint. The turbocharged 3.8 became standard and would continue to be refined with fuel injection and intercooling. In 1987 it reached 245 hp.

1987 also offered a lightweight WE4 (Turbo T) option which is extremely rare today. Only 1,547 of this variant were produced. They were painted black and treated to the same blackout package as the Grand National, including bumpers, grille, headlight and taillight trim. The differences between a WE4 and the base Grand National were the interior trim package, wheels, exterior badging, aluminum bumper supports, and aluminum rear brake drums as opposed to the Grand National’s cast iron. The rear spoiler was only available as a dealer installed option.

By 1985, the Grand National was acquiring a reputation as a modern muscle car, but the days of the G-body were numbered. For the final year, 1987, Buick introduced the GNX at a US$11,000 premium. Produced by McLaren/ASC, Buick underrated the GNX at 275 hp and a very substantial 360 lb-ft (488 N·m) of torque which gave this car a 0-60 time of 4.7 seconds. This was created so as to be “Grand National to end all Grand Nationals,” as the next model year converted the chassis to front-wheel drive, which, Buick engineers admitted, simply wouldn’t be able to put down that much power. Changes made included a special Garrett ceramic-impeller turbocharger connected by a ceramic-coated pipe to a better intercooler. A special computer chip, low-restriction exhaust, and reprogrammed Turbo Hydramatic 200-4R transmission with a custom torque converter and transmission fluid cooler completed the drivetrain modifications. Exterior styling changes include vents located on each front fender, 16 inch black mesh style wheels with VR-speed rated tires, and deletion of the hood and fender emblems. The interior changes of the GNX included a serial number on the dash plaque and a revised instrument cluster providing analog Stewart-Warner gauges, including an analog turbo boost gauge.

The acceleration performance of the GNX outpaced the factory’s power claims: 0-60 mph (97 km/h) took just 4.7 s with a 13.4 s/104 mph (167 km/h) quarter-mile. According to contemporary sources, these numbers made the GNX the fastest production sedan ever built. This claim is somewhat controversial—the car had two doors but its interior volume and structure made it a sedan rather than a coupe, and just 587 examples were built. GNX #001 is currently owned by Buick and sometimes makes appearances at car shows around the US. Although many quicker cars have been built, including a number of quicker modern sedans, its performance was truly impressive for the time. A contemporary Porsche 930 hit 60 mph in 5.0 seconds and ran the quarter mile in 13.6 seconds, roughly equivalent to the GNX , which cost much less and could out-accelerate the naturally-aspirated 911 of the day. Ironically, many believe that these performance numbers were the reason the GNX was axed. GM didn’t want one of its own cars outperforming its flagship, the Corvette, and pulled the plug on the Buick program. The muscle cars of the 1960s had the power to beat the GNX , but the tires of the time could not transform this into speed, not to mention the numerous techniques employed in the GNX allowed the car to transfer all the power to the ground, such as a ladder bar that ran from the mid-section of the car to the rear axle, so as to increase traction. This is also the reason why a GNX will actually lift the rear end up when the car is about to launch heavily. The GNX never made much of a road-track competitor to cars like the 911, but it could certainly hold its own on a drag strip.