There was no Grand National in 1983, only a T-Type model; 3732 were produced (190 hp (140 kW) at 1600 rpm and 280 lb·ft (380 N·m) of torque at 2400 rpm).
In 1984 the Grand National returned in all black paint. The turbocharged 3.8 L became standard and was refined with sequential fuel injection, and boasted 200 hp (150 kW) at 4400 rpm and 300 lb·ft (407 N·m) of torque at 2400 rpm. Only 5,204 Turbo Regals were produced that year, only 2000 of which were Grand Nationals.
In 1986, a modified engine design with intercooling boosted the performance even further; in 1987 it reached 245 hp (183 kW) and 355 lb·ft (481 N·m) of torque. Buick dropped the T-Type package for Regal in 1987. There were only 7,896 Turbo Regals produced in 1986. In 1987, when Turbo Regals reached their peak in popularity, a total of 27,590 Turbo Regals were produced through December.
1987 also offered a lightweight WE4 (Turbo T) option. 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. 1987 was the only year that the LC2 Turbo option was available on any Regal, making it possible to even see a Limited with a vinyl landau roof and a power bulge turbo hood.
For the final year, 1987, Buick introduced the GNX at $29,000. Produced by McLaren/ASC, Buick underrated the GNX at 276 hp (206 kW) and a very substantial 360 lb·ft (488 N·m) of torque. 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 would not be able to put down that much power. Changes made included a special Garrett turbocharger with a ceramic-impeller blowing through a more efficient intercooler and a specially coated up pipe. A GNX specific EEPROM, low-restriction exhaust with dual mufflers, reprogrammed Turbo Hydramatic 200-4R transmission with a custom torque converter and transmission cooler, and unique differential cover/panhard bar included more of the performance 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 GNX was claimed as the fastest production sedan ever built at that time. GNX #001 is currently owned by Buick and sometimes makes appearances at car shows around the US. The GNX had 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.
1987 Buick Regal Grand National
1987 Buick Turbo Regal "WE4 package"
G-body Buick Regal
1978-1981 Buick Regal
The stealthy appearance of the all-black GNX and Grand National, coupled with the fact that the Grand National was initially released during the height of Star Wars fever, earned it the title Darth Vader Car (Car and Driver covered the GNX model's introduction with the headline "Darth Vader, your car is ready," a phrase more recently attributed to the Maybach Exelero). The line was also used with the 1994 Chevrolet Impala SS years after the GNX was discontinued.
The Grand National returned briefly to the headlines in 2003, when actor Sean Penn's car was stolen with several guns inside. Also, actress Carmen Electra bought her then rock star husband Dave Navarro a 1987 Grand National as a present. A 1987 GNX is featured in the new video game midnight club Los Angeles.