The 1987 3.8L Turbo V-6. Other than the GNX unit that received a better turbocharger, larger intercooler, and better engine management,
this was the Turbo’s high water mark
More on the Buick Grand National and GNX
In 1982 the car we call the Grand National debuted, named for the NASCAR Grand National Series. The 1982 cars were not painted black. All were a charcoal gray Regal that were shipped to Cars and Concepts for finishing. Of the 215 Grand Nationals produced in 1982, 35 were were equipped with the turbocharged 3.8 L V6 engine.
For 1983, the Grand National was absent. However the sport coupe model was renamed the T Type. It was fitted with an upgraded 3.8 L Turbo developing 190 HP @ 1600 rpm and 280 lb⋅ft of torque at 2400 RPM, making it an able performer. (As a comparison, the 1983 Ford Mustang produced 175 hp @ 4200 rpm and 245 lb⋅ft of torque @ 2400 RPM). The 1983 Regal T Type featured tube headers, Hydro-Boost II brakes, 200-4R 4-speed overdrive transmission and 3.42 rear axle. The T Type was relatively popular, with 3,732 produced. The “T Type” moniker had been used on other Buicks, starting with the Riviera in 1981, prior to that it had been called the “S Type”.
For 1984, the Grand National returned, now (finally) in all black paint. The turbocharged 3.8 L was standard equipment in this and the T Type. It was refined even more, with sequential fuel injection, distributor-less computer-controlled ignition, and now boasted 200 HP @ 4400 rpm and 300 lb⋅ft of torque @ 2400 rpm. In total, only 5,204 turbo Regals were produced that year, of which only 2,000 of which were Grand Nationals.
This being the first year of production of the all black Grand National and as it was fitted with computer-controlled sequential fuel injection and distributor-less ignition, many consider this as the year that started the development of the legendary Grand National, even though the name had existed previously. The performance of this package was exceptional for a V-6 equipped car with 1⁄4 mile performance listed at 15.9 seconds. All Grand Nationals had the Lear-Siegler made cloth and leather interior that was only available for this year, as later Lear Siegler seats were all cloth. About 200 of the 1984 Grand Nationals were produced with the Astroroof option, making these the rarest of the Grand Nationals.
The 1985 Grand National was a clone of the 1984 unit, using the same Turbo V-6 as 1984, and total Turbo production dipped to 4.169. Though unchanged, the Grand National was receiving cult status among the reinvigorated muscle car clan. Buick finally deemed it significant to create an advertising campaign around it, with the rock group Delaware Destroyers doing “Bad to the Bone” over images of the Grand National.
For 1986, a modified engine design with an air-air intercooler boosted the performance 235 HP @ 4000 RPM and 330 lb⋅ft of torque @ 2400 RPM. The torque increase was felt in a much better acceleration time, dropping the car into the mid-14s in the 1/4 mile. The 1986 Grand National’s production of 5,512 versus the T Type’s 2,384 was the first time the grand National exceeded the T Type in buyers. There were only 7,896 turbo Regals produced in 1986.
In 1987, power and torque was increase to 245 @ @ 4000 RPM and 355 lb⋅ft of torque @ 2400 RPM. Recognizing that the Turbo Regal buyer was more in love with the Grand National’s aggressive looks, Buick dropped the T-Type package for Regal this year. However the 3.8 Turbo was available as an option on all Regals this year, making for some interesting deliveries, such as a fully loaded Regal Limited with the 3.8 Turbo! Turbo Regal Limiteds were one of the rarest models with 1,035 produced. With the option of Turbo power across the board, turbo Regals reached their peak in popularity, a total of 27,590 through December 1987, past the model year! Strangely, the rear spoiler was only available as a dealer-installed option.
It was also possible to order the 1987 Regal T with the 5.0/307 V-8 instead of the turbo 3.8 Turbo V-6. The 1987 model would be the end of the manufacture of the RWD “G-Body” Regal, however GM had to extend the build of the Grand National to meet customer demand into December. The models produced between September and December of that year received a window sticker “1987½ Buick Grand National”.
The WE4 Option
For 1987, a lightweight WE4 option was offered (called “Turbo-T”). Only 1,547 of this variant were produced. The look of WE4 Turbo T compared to the Grand National was in the interior trim package, wheels, exterior badging. But the big difference was in aluminum bumper supports, and aluminum rear drum brakes. Those pieces and the lighter interior made the Turbo T a faster car.
In the final year, of RWD Regals, with a desire “to go out with a bang”, Buick introduced the limited production GNX, for “Grand National Experimental”, at $29,900 ($72,500 in 2022 dollars). Made in partnership with McLaren Performance Technologies/ASC, standard Grand Nationals were were produced by Buick and then sent off to McLaren and upgraded into the Buick GNX. Changes made included a special Garrett AiResearch T-3 turbocharger with a ceramic-impeller pushing air through a more efficient and larger capacity intercooler. A “Cermatel (ceramic-aluminum) coated” input pipe connected the intercooler to the engine. Also, GNX specific performance computer, low-restriction exhaust with dual mufflers, reprogrammed turbo Hydramatic 200-4R transmission with a custom torque converter and transmission cooler, and a unique differential cover/Panhard bar, that was added for increased traction, were the key performance modifications.
Exterior styling changes included vents located on each front fender, 16″ 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 Stewart-Warner analog gauges, including a turbo boost gauge.
Buick underrated the GNX at 276 hp @ 4400 RPM, and a substantial increase in torque to 360 lb⋅ft @ 3000 RPM. This figure was revised to 300 HP and 420 lb⋅ft of torque. One drag strip performance test resulted in a 1⁄4 mile time of 12.7 seconds at 113.1 MPH. Buick produced only 547 GNX models. GNX #001 is the 1986 prototype and is currently owned by Buick and makes appearances at car shows around the US.