Another dealership with an unsold musclecar, this time an '87 GNX, last one was a '69 Daytona

http://articles.latimes.com/2010/dec/10/business/la-fi-autos-buick-gnx-20101211 for the GNX with 136 miles. The Los Angeles dealership bought it from GM, tried once or twice to make a killing by auctioning it off, and never succeeded. They eventually decided to keep it as an investment they can one day cash in.

http://www.hemmings.com/newsletter/newsletter.html?volume=1&issue=45 for the 1969 Charger Daytona that kept getting shifted between two dealerships but never sold from it's Virgina home... til in 2004 someone recalled they had a gold mine stuffed away in the attic of the dealership and it went to Mecum auctions. I read about it in a magazine, but can't recall much about it.

tipped to the GNX from Jalopnik

The rare and unusual Buick, the 1987 GNX, 13.43 in the 1/4 from the factory. Wow.

A Gnx delivered 275 bhp and a whooping 360 lb-ft.

It also received a special rear axle housing cover made of aluminum (with GNX embossed on it) that serves as an additional strengthening element and point for the torque bar. For even more strengthening, the car body received special structural reinforcements in the form of "behind the back seat bracing" and special chassis (steel cross member between the chassis rails) bracing.

The GNX was the only Regal to ever receive 16 inch wheels. The wheels were made of a lightweight alloy and the rear wheels were wider than the front. The GNX came with P245/50VR16 tires in front and P255/50VR16 tires in the rear.

Inside, the dash had a special Steward Warner analog gauge package.

All GNXs received a special numbered plaque mounted on the passenger side dash which identified the number of that particular car (1-547).

But all of this came at a price. The cost of the GNX option was a whopping $10,995, which resulted in a final MSRP of $29,900.

Even more rare are the Buick Regal T-Type "Special T." These models had a Grand National exterior, but a Regal T-Type interior.

Production: Grand Nationals: 20,193
GNX: 547

Engines: Grand National: 3.8L V6 Turbo 245 bhp @ 4400 rpm, 355 ft-lb @ 2000 rpm.

GNX: 3.8L V6 Turbo 276 bhp @ 4400 rpm, 360 ft-lb @ 3000 rpm.

Performance:
Grand National: 1/4 mile in 14.23 seconds @ 98 mph.
GNX: 1/4 mile in 13.43 seconds @ 103 mph.

http://www.musclecarclub.com/musclecars/buick-grandnational/buick-grandnational.shtml