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Not a Delta!

but it does have a turbo

buick gnx

This is an interesting car, the 1987 Buick Regal Grand National GNX.

It's a GM V6, turbocharged and intercooled, with rear wheel drive. It's a very rare car, now worth lots of $$$, here's the story....

nascar buick regal

Like a Delta, the Buick Regal started life as basic compact family car. This 2nd generation model introduced in 1978, had been downsized and simplified from the previous series, and was an unlikely candidate for performance treatment.

The GM V6 engine and tooling had been sold to Jeep in 1970, passed to AMC, then bought back by GM in 1974.

GM saw a future for the V6, but it wasn't happily accepted by the public.

The popular GM muscle cars like 'The Judge' of earlier years, were fitted with a 390 hp 428cu V8 motor.


In 1982, the Regal Grand National debuted, which was named for the NASCAR Winston Cup Grand National series. Buick had won the Manufacturers Cup in 1981 and 1982, and wanted to capitalize on its success: "What wins on Sunday, sells on Monday". These 1982 cars were not painted black, which may confuse those not familiar with them. All started out as charcoal grey Regals that were shipped off to a subcontractor for finishing.

I can't mention 'The Judge' without it's starring

role in 'Two Lane Blacktop'. Here's Warren Oates,

him and the car both looking for trouble!

the judge
Warren Oates in The Judge
grand national t top

This was an unusual low key styling exercise for a US performance car, a bit European in tone. With a good solid stance.The small 'Opera windows' were very US though!

This model was only produced in black too, with no side stripes, and no chrome..

The car shown here is a T bar roof model, which is now a very valuable car

Originally intended for a run of 100 units, Cars and Concepts of Brighton, Michigan, retrofitted 215 Regals with the GN package.

The wheel opening moldings and rocker panel moldings were blacked out using black vinyl tape. Finally, a front air dam and rear spoiler were installed. On the inside, special "Lear-Siegler" seats were installed. These seats are fully adjustable and were covered with silver brandon cloth with black vinyl inserts. The front seat had Buick's "6" emblem embroidered onto them. To finish it off, a special clock delete plate was added to the instrument panel which contained the yellow and orange "6" logo and the words "GRAND NATIONAL BUICK MOTOR DIVISION.")

The '82 GN came with a naturally aspirated 4.1 L V6 engine with 125 hp (93 kW) at 4000 rpm and 205 lb·ft (278 N·m) of torque at 2000 rpm. Of the 215 Regal Grand Nationals produced in 1982, at least 35 were based on the Buick Regal Sport Coupe package with the turbocharged 3.8 V6 engine with 175 hp (130 kW) at 4000 rpm and 275 lb·ft (373 N·m) of torque at 2600 rpm. There were only 2022 Sport Coupes produced in 1982, and the number of cars with both the GN and Sport Coupe packages is estimated to be less than 50.

buick grand national rear 1/4

This 1984 Buick was one of the first cars with computer controlled fuel injection, and no distributor.

It was very advanced for the time, and led the way in ECU controlled engine management systems.

You'll see below the turbo boost level is 15psi,

the same as our cars.

In 1984 the Grand National returned in all black paint. The turbocharged 3.8 L became standard and was refined with sequential fuel injection, distributor-less computer controlled ignition, 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. Because this was the first year production of the computer controlled Sequential Fuel Injection and Distributor-less ignition, this is often considered the year/model that started the development of the legendary intercooled Grand Nationals. The performance of this package was well ahead of its time and the “Little V6” easily kept up with the bigger V8’s. Quarter mile performance was listed at 15.9 seconds at stock boost levels of 15 psi (1.0 bar), while for the same year, the Chevrolet Camaro was listed at 17.0 and the Chevrolet Corvette at 15.1 seconds. Soon, performance enthusiasts determined the modifications that worked and the Grand Nationals easily broke into the 13-second territory. All Grand Nationals for this year had the Lear Siegler made cloth/leather interior which was only available for this year. An estimated 200 of the 1984 Grand Nationals were produced with the T-Top option which makes these the rarest of the Grand Nationals.


1986 Grand National

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 and opted for a "T" sport package instead. 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, with those models produced between September and December of that year window stickered as "1987½ Buick Grand National" vehicles.

For the last models there was a different Garrett AiResearch turbo with a larger housing, dynamic oil seals for less drag and a ceramic turbine, which was lighter. The shape and number of fins in the intercool­er were changed for greater fin density and effectiveness. There already was an engine oil cooler in the Grand Nationals, and the GNX added a cooler for transmission fluid, though that's the only change to the Turbo Hydramatic 200 4R.

Off the dyno the GNX engine was up 55 bhp from the standard Grand National's rating to 300 at 4400, while torque climbs from 355 to 420 at 2400 rpm.

In the picture to the right, you can see the straight induction tract to the high mounted turbo, coil packs and fuel injection block.

This is all really advanced for that time, it must have been difficult convincing GM to finance a project with limited sales appeal, but also needing lots of research and risking reliabilty issues.

buick grand national engine bay


Buick had already reached the limits of the Regal's suspen­sion with the Grand National, so the GNX is beefed up still more. The rear suspension's production lower control arms stayed, joined now by a Panhard rod and a very substantial longi­tudinal torque bar. Attached to a crossmember forward of the differential, the bar looks like an elongated vee laid on its side with four vertical braces. The open end of the torque bar is firmly bolted to the top and bottom of the differential.


Buick said one major reason for the 124-mph limit on the Grand National is the lack of V-rated P215/65R-15 tires. The GNX got the proper rubber, Goodyear Gatorbacks measuring P245/50VR-15s for the front wheels and P255/50VR-15s at the back. To fit inside the Regal wheel wells, the housings had to be enlarged and were trimmed on the outside with wheel plastic lip moldings. Buick kept the rev limiter set for 124 mph, howev­er, figuring that's a reasonable limit. . . and probably remembering this was still a Regal chassis. Incidentally, rumor has it this top speed limit did not apply to the Grand Nationals bought by the FBI.

There are a few other changes that mark a GNX. The stock instruments were replaced with white-on-black dials from Stew­art Warner, perhaps to remind the driver of the no-nonsense nature of the car. To help exhaust some of the heat build-up from the 300 bhp V-6, there was a row of vents on each fender. On the grille and trunk lid were GNX badges. As with the standard Grand Nationals, all GNXs were available in any color, as long as it's black.

buick grand national back axle

This picture shows the back axle on the Buick. The lovely cast alloy diff cover has top and bottom mountings for the Y shaped torque bar mentioned above. The front bar mounting is a long way down the car at the centre cross member.

This Buick's next model replacement was front wheel drive, and already on sale with this GNX. So this was the last RWD compact from GM for some time.

The stealthy appearance of the all-black GNX and Grand National (and the resemblance of its grill to his helmet's mouthpiece), coupled with the fact that the Grand National was initially released during the popularity of the Star Wars movies, earned it the title "Darth Vader's Car". Car and Driver magazine covered the GNX model's introduction with the headline "Lord Vader, your car is ready." Due to the six cylinder engine, the Buick make, and the black paint Grand Nationals were sometimes referred to as the "Dark Side". The "Dark Side" contrasted with the more common V8 Mustangs and Camaros that were popular at the time.

This Buick Grand National is for sale at Napoli Classics in USA for $65000, offers invited. Click on the picture to visit site.

Apparently it's very easy to paint any old turbo V6 Buick Century black, and pass it off as a Grand National.

So caution is required if you're thinking of buying one of these Buicks, just like a Delta.

This Buick was a rare project for a mainstream maker, one that is unlikely to be repeated. It has a lot in common with our Deltas, with the advanced electronics, forced induction, humble beginnings, and kick ass performance.

There's a film about developing this Buick called

'Black Air'.

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