The Buick Grand National was a special enough car, running from 1982 to 1987, at a time when performance was eschewed in favor of lower emissions, for the sake of healthier air. The muscle car era had just ended, but the oil embargo crisis was also winding down to tired sighs of relief.

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So when the Buick Grand National stormed in, it kickstarted America’s love with both performance and speed. No surprise when it became a crowd favorite. And when it took a curtain call in 1987, it didn’t go out with a whimper, but with a bang. What are we talking about? The Buick GNX, and ten things you may not have known about it.

10 The X Is Not For Extreme

Launched as a final curtain call for the Buick Grand National, The Buick GNX expanded to Grand National Experiment, not extreme as some people have a penchant for thinking. Buick, as a GM marque, was always more about upscale coupes and sedans, though the Regal had won over NASCAR and its likes. The Grand National was a cool enough car, but with the GNX, Buick took Chevrolet, or rather the Corvette head-on. And it took Corvette a little while to recover, though all the GNX did was take the G-body out with a bang as opposed to a whimper. This was a wonderful experiment indeed.

9 The GNX Was Not Well Received

Well, certainly not by Buick itself. While it was the idea of Dave Sharpe (Buick’s Chief Engineer) and Mike Doble (Buick’s Advanced Concepts Manager); the general manager Ed Mertz wasn’t onboard with it at all. The marketing manager, Darwin Clark was all for it but Dick Payne, the comptroller was livid at the idea.

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Yet somehow, with many other top executives at Buick straddling the fence; the project kept going. While there were no written rules about how a Buick should be like, it was never meant to be as fast as a Corvette. And definitely not faster. So the GNX was a bit scary for Buick, internally.

8 More Than Just A Grand National

The Grand National was one of the greats – while it may not have lasted in the first few positions in long races, in shorter races it was near unbeatable. It all began in 1982 when Buick began with a 3.8-liter pushrod engine, which was a 90-degree V6. The disbalance was a problem so they split the crankshaft and added more balance to it. This evened out the firing frequency. A Bosch fuel injector, many other advancements and build-ups later – the Grand National was finally ready. This was a car touted to eat Mustangs, Camaros, and Corvettes too. And then they brought in the GNX that ate the Grand National for breakfast.

7 The GNX Was A McLaren Baby Too

To turn the Grand National into the GNX, Buick needed help from more than just the big brains at Buick. So they roped in McLaren who simply loved doing projects like these. And then they got in ASC as well. For the GNX to be real and fast, the body had to be modified and the rear suspension was retouched.

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The spin time of the turbine was too slow, so they added an intercooler to tackle that. Bigger and better tires went in, and the Grand National turned into the Grand National Experiment. McLaren/ASC knew their V6s, so they made the GNX the best a V6 could do for that time.

6 The Creators Had Some Fun With It

Buick didn’t just make the GNX and start selling it. First, they raced it at Milford, which was like a holy proving ground for the GNX. The project was finally blessed by Mertz and Bill Hogland, who was running Buick-Oldsmobile-Cadillac at the time. Then, they headed off to a long drive with three Grand Nationals and two GNX prototypes. The ultimate route turned out to be Phoenix-Grand Canyon-Nevada-Vegas-California-Death Valley. From time-to-time, they collaborated with the local cops who drove beside them for safety. Then ASC pulled a fast one on Buick – without telling Buick, they entered the GNX prototype for a dirt race. And the GNX prototype killed it, sparking an ever-growing interest in spectators.

5 The Prototype Generated A Furor

That little dirt track show made the Buick GNX the hottest thing in town, even though Buick had not officially announced its sales. Journalists called Buick to ask about release dates and distributorship channels. People from all over the world called or wrote in to find out about the GNX.

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Remember that this was 1987, and the Internet was not the viral beast it has become today. That single dirt track race spearheaded the furor that was the GNX demand. Everyone wanted one, even though it was priced a lot higher than the Grand National. That said; as good as the Grand National was, it had nothing on the GNX.

4 And Yet, Not Many GNX were made

The Grand National was on its way out. 1987 was the end of an era, of a car that had ruled Daytona and was also a pace car of the Indy 500. When the Grand National people at Buick thought of the GNX, they had one thought in mind – to make a Grand National end all Grand Nationals. Like a tribute to the legacy of the car, but with the tribute setting the bar even higher than before. Initially, they decided on making 200 GNXs, as a tribute to Daytona 200. Soon, the number became 500, for Indy 500. Finally, another 57 were added as dealer special rewards, taking the total number of GNXs produced to a mere 547.

3 The GNX Commanded A Steep Price

At about $29,000; the Buick GNX was dearer than the $19,000 Grand National. Those who could afford that extra $10,000 did drive home their GNX; their newest pride and joy. And yet, even then, with only 547 of these in town – some people made a second-sell killing out of these, selling brand new buys at $80,000-$90,000. Even now, with the utter rarity of these cars – finding them on the classic car bazaar is a task and an expensive find at that. While you can find a well-used one for a little under $100k, a barely used GNX can still command almost $200k on the market.

2 The Unique Production Number Was Displayed

Each 547 of the 1987 Buick GNXs came with their unique production number. This was engraved on special plates that were prominently attached to the car – at the dashboard, at the fan cover under the hood and even on the engine cover, with a GNX logo beside it. Highly coveted to date, these production numbers also make it easy for buyers to trace the veracity of the GNX they may be interested in getting. Remember, this was the car that officially jetted 276 horses, though many say the actual ponies were over 300. Add to this a huge 360 ft-lb of torque and the GNX was truly a class apart.

1 That Original GNX Jacket

A GNX still demands a cool price – in 2015, a 1987 GNX went up at auction in Palm Beach, Florida and fetched a cool $165k. And it's not just the car that manages to sell so well. Every 1987 Buick GNX came with a special jacket for the owner, so created by a Californian race-gear maker. This jacket bore the GNX logo on the front and the back, which was embroidered with panache. Many of these jackets have been lost or damaged over time. However, every now and then, a mint condition jacket finds its way on eBay or other such auction sites. Not surprising that they manage to fetch $4000 upwards from GNX fans.

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