The Buick GNX (Grand National Experimental) is a limited-production, high-performance version of the Buick Regal, built for the 1987 model year. It's famously known as the "Darth Vader" of muscle cars due to its menacing all-black appearance and was designed to be the ultimate send-off for the rear-wheel-drive G-body platform. In short, the GNX is a legendary American performance sedan celebrated for its brutal acceleration and is now a highly sought-after collector's car.
Developed in partnership with ASC/McLaren, the GNX was more than just a trim package. It featured significant modifications over the standard Grand National to address turbo lag and improve overall performance. A key upgrade was the addition of a Garrett AiResearch T-3 turbocharger and a dedicated intercooler, which helped the 3.8-liter turbocharged V6 engine produce an underrated 276 horsepower and a massive 360 lb-ft of torque. Many experts believe the actual output was closer to 300 horsepower.
The GNX's performance figures were staggering for the era, easily rivaling contemporary supercars. The following table highlights its key specifications and how it compared to some notable performance cars of 1987.
| Specification | Buick GNX | Ferrari F40 | Porsche 911 Turbo | Chevrolet Corvette |
|---|
| 0-60 mph Time | 4.6 seconds | 3.8 seconds | 5.2 seconds | 5.7 seconds |
| 1/4 Mile Time | 13.5 seconds | 11.8 seconds | 13.7 seconds | 14.5 seconds |
| Engine | 3.8L Turbo V6 | 2.9L Twin-Turbo V8 | 3.3L Turbo Flat-6 | 5.7L V8 |
| Horsepower | 276 hp (est. 300+) | 478 hp | 282 hp | 240 hp |
| Torque (lb-ft) | 360 lb-ft | 425 lb-ft | 278 lb-ft | 340 lb-ft |
| Total Produced | 547 | 1,315 | 4,614 | 30,632 |
Beyond the engine, the GNX received a redesigned exhaust system, a modified Turbo-Hydramatic 400 transmission with a special torque converter, and a limited-slip differential. Externally, it was distinguished by its flared fenders, functional hood vents, and iconic GNX badges. Only 547 units were ever built, making it exceptionally rare. Today, well-preserved examples regularly sell for over $100,000 at auction, a testament to its enduring legacy as one of the most potent American cars of the 1980s.
