1987 marked the swan song for the Buick Regal Grand National and the one-year-only Buick GNX. Resplendent in haunting glossy black, this factory special featured black basket-weave wheels with polished lips, a black and gray cloth interior with stylized Buick 6 logo embroidered in the headrests. The standard 1987 Grand National made 245 turbocharged horsepower from its 3.8-liter V6, but the GNX was far from standard.
Buick partnered with ASC/McLaren Performance Technologies to convert 547 copies of the Grand National into skulking street beasts known as the GNX (Grand National Experimental). The Buick GNX differed from the Grand National in that it had an upgraded Garrett T3 turbocharger, freer flowing heads, improved engine management controls, a larger air-to-air intercooler, and a less restrictive exhaust. Claimed power output was laughingly underrated at 276 horsepower and 360 pound-feet of torque.
The Buick GNX had more than just the underhood changes hidden up its dark sleeve. The body was stiffened, a transmission cooler added, and an improved rear suspension design featuring stiffer springs, a Panhard rod, torque arm, and an additional frame cross member. The performance improvement was impressive, allowing the GNX to lay down a zero-to-sixty time of just 4.6 seconds, and to smoke through the quarter mile in the low 13-second range, enough to embarrass GM’s flagship Corvette.
For those with sharp eyes, there were a number of unique styling cues that distinguished the Buick GNX from its Grand National stablemate. Composite fender flares, functional fender vents over the front tires to help cool the engine compartment, and the aforementioned larger basket-weave 16-inch black wheels with polished aluminum lips. GNX badges appeared in the grille, trunk lid, and on the wheel center caps.
The interior featured a serial number plate that was mounted on the passenger side of the dash. Standard gauges were swapped for Stewart-Warner units, with gauges for oil pressure, coolant temp, and boost level housed in a modified cluster.
Our feature 1987 Buick GNX is #41 of 547 produced. First delivered to Bayview Buick GMC of Port Richey, Florida, it has covered just eight hundred sixty-five miles from new. With the exception of some discoloration at the front and rear bumper urethane filler panels, GNX #41 is as new.
This time capsule Buick GNX is accompanied by build sheets, the window sticker, purchase documents, owner’s manuals, service records, a clean Carfax report, and a clean Illinois title. It is now for sale on Bring A Trailer, with brisk bidding and six days left at the time of writing.
Subscribe to GM Authority for more Buick GNX news, Buick Regal news, Buick news and around-the-clock GM news coverage.
Comments
>$200,000 all day long…
Pain Maker!!!
My wife and I go to dozens of car shows in the summer and I have only ever seen one GNX in person. Very rare!
Go the Buick GS Nationals every May & you will see them:)
It’s a shame no one got to drive and enjoy this car.
Someone has the chance now
This one is a keeper! I will be listing my GNX this summer with a bit over 1,000 miles. All original with documents, window sticker, pristine. Watch for it.
Hey GNX guy! I have been seeking a GNX for my fathers son. He is a classic collector and has been bugging me to help him find one for sale. If you have one feel free to to reach out. BTW I am Noel.
Hello there! I may list it around July.
Always loved the GN/GNX, Tupperware dashboard notwithstanding. One of GM’s great sleepers.
This will sell for a LOT.
Hagerty books these at $288,000. They are selling for over $300,000 now, and that is for the low 4 digit mile ones. What will a single digit mile one sell for now??
What is the actual dyno hp of these? Someone has to have tested one by now.
380-400 HP at the crank. So about 320-340 HP at the rear wheel. They were not all exactly the same.
One thing I would do would be to take it to a chassis Dyno tuner and find out.
At the rear wheels.
I remember one specifically 320 RWHP at R.C.’s shop. Not modified or altered in any way.
I bought a new ‘86 GN in Denver, still have it. I was active in the Buick club then, and there was a guy with a new GNX also in the club. We met at the drag strip a couple of times and the GNX wasn’t notably faster/quicker than our regular GN’s. The thin Colorado air certainly affected engine power (18% reduction at 6000’), but it affected all of us equally. I don’t want to deflate the GNX mystique, as it is a beautiful and desirable car, but realistically “350-400 hp at the crank” in stock form is a stretch. Just sayin’.
THERE’S A BIG DIFFERENCE!! I’ve owned 3 turbo Buicks ( 1 GN & 2 GNXs) so I KNOW. In ’86, I bought a NEW GN. In ’87 I traded in my GN on a NEW GNX. In ’89, I bought ANOTHER GNX (while still having the first one).
The differences are these: from a standing start (with brake torque), the GN sinks in the back while the rear of the car fishtails until it FINALLY steamrolls STRAIGHT and ahead.
The GNX LIFTS UP in the back. There’s actually little to no wheelspin and its actually smoother than the GN. You really don’t even think you’re going that fast until you look at the speedo and see that this car is MOVING.
The GNX handles WAY BETTER than the GN. With the larger tires and revised suspension, the GNX handles almost like a sports car.
With the 2 separate mufflers versus the large single one in the GN, the GNX sounds HEALTHIER.
The GNX is a fully loaded car. MOST GNs weren’t. I’ve also seen MANY “strippers”. GNs with little to no options – basic models with roll up windows/ NO posi (it was an option).
The GNX started life as a fully loaded GN and then was sent to ASC/ McLaren for mods – just like it was done in the ’60s.
UNFORTUNATELY, the GNX had the same lousy paint and reliability issues as the GN and other GM products.
Its also GREAT to drive such a rare car.
But all GNXS DID NOT PERFORM THE SAME. My first car was quicker than my second.
If there’s a “mystique” its because the car itself is so rare. HOWEVER, after 4 years of production, less than 30 thousand Grand Nationals were built, making them rare too.
Through the years, with so many cars BEAT UP (raced heavily – driven hard)/ WRECKED/ DESTROYED, there’s a lot less GNs around.
NOTE: the ONLY difference between the ’86 & ’87 GN is THE GRILLE. Although the ’87 is rated at 10 hp higher, there was NO difference in the engines. Buick played with the horsepower ratings.
FINALLY, A fellow GN/GNX owner that KNOWS that there IS a big difference between the GN’s and GNX’s, hence the $10,995 GNX option. (Huge back then) Most people do not realize all GNX’s did not have the same exact horsepower as many things were done by hand including the adjustable wastegate at ASC McLaren. There are a lot more differences between the two but you have summed it up well!
I agree, they likely have around 300 hp. If you cranked up the boost to around 18lbs on a stock gn they could keep up with a gnx.
But if you increased the boost on the GNX, we would be right back where we started.
SOLD for $225k.