The Buick Grand National and GNX are two iconic American muscle cars that share a common lineage but have distinct differences. Both models were based on the Buick Regal platform and featured turbocharged V6 engines, but the GNX (Grand National Experimental) was a limited-edition, high-performance version of the Grand National. Understanding the key distinctions between these two vehicles is crucial for automotive enthusiasts and collectors alike.
The Buick Grand National was produced from 1982 to 1987, with the most powerful versions appearing in the later years. It gained a reputation for its all-black exterior and impressive performance, especially considering its era. The GNX, on the other hand, was introduced in 1987 as the ultimate expression of the Grand National concept, with significant upgrades to power, handling, and exclusivity.
| Feature | Grand National |
|---|---|
| Production Years | 1982-1987 |
| Engine | 3.8L Turbocharged V6 |
| Horsepower (1987 model) | 245 hp |
| Torque (1987 model) | 355 lb-ft |
| Production Numbers | Approximately 20,000 (1987) |
Engine and Performance
The most significant difference between the Buick Grand National and GNX lies in their engine specifications and performance capabilities. While both cars utilized a turbocharged 3.8-liter V6 engine, the GNX received substantial upgrades that set it apart from its predecessor.
The 1987 Buick Grand National, which was the most powerful version of the standard model, boasted 245 horsepower and 355 lb-ft of torque. These figures were impressive for the time, especially considering that the Grand National outperformed many V8-powered muscle cars of the era.
In contrast, the GNX took performance to another level. Buick collaborated with McLaren Performance Technologies/ASC to modify the engine and other components. The result was a powerplant that officially produced 276 horsepower and 360 lb-ft of torque. However, many experts believe these figures were understated, with actual output potentially reaching 300 horsepower and 400 lb-ft of torque.
The performance difference was notable:
- The Grand National could accelerate from 0-60 mph in about 5.5 seconds
- The GNX could achieve the same sprint in approximately 4.7 seconds
These improvements were achieved through several key modifications:
- Larger Garrett T3 turbocharger with a ceramic impeller
- Larger capacity intercooler
- Revised engine management system
- Low-restriction exhaust system
Exterior and Styling
While both the Grand National and GNX shared a similar overall appearance, the GNX featured several distinctive exterior elements that set it apart from its more common counterpart.
The Grand National was known for its menacing all-black exterior, which became its signature look. It featured a simple, muscular design with minimal badging and chrome accents. The car’s appearance was part of its appeal, presenting an understated yet aggressive stance.
The GNX, however, took this design and added several unique elements:
- Functional fender vents on the front fenders to help dissipate engine heat
- Composite fender flares to accommodate wider tires
- 16-inch black mesh wheels with GNX center caps, compared to the Grand National’s 15-inch wheels
- GNX badges on the grille, trunk, and wheel centers
- Deleted hood and fender emblems for a cleaner look
These exterior modifications not only enhanced the GNX’s appearance but also served functional purposes, improving cooling and handling capabilities.
Interior Features
The interiors of the Grand National and GNX shared many similarities, but the GNX received several upgrades to reflect its premium status and performance capabilities.
Both models featured:
- Black and gray upholstery
- Power windows and locks
- Air conditioning
- Tilt steering wheel
However, the GNX distinguished itself with:
- Stewart-Warner analog gauges, including a 160 mph speedometer and 8,000 rpm tachometer
- Special turbo boost gauge
- Oil pressure and coolant temperature gauges
- Numbered dash plaque indicating the car’s production sequence out of 547 units
- Lack of T-tops or sunroof option to maintain structural rigidity
These interior enhancements gave the GNX a more premium and performance-oriented feel compared to the standard Grand National.
Suspension and Handling
Another area where the GNX significantly differed from the Grand National was in its suspension setup and handling characteristics. While the Grand National was known for its straight-line speed, the GNX received upgrades to improve overall handling and performance.
The GNX featured:
- Specially calibrated suspension with progressive rate springs
- Longitudinal torque arm to help plant the rear tires during hard acceleration
- Panhard rod and track bar to improve rear axle location
- Larger diameter sway bars
- Specially tuned shocks
These modifications resulted in improved handling and stability, particularly during high-speed maneuvers and cornering. The GNX was not just a straight-line performer but a more well-rounded sports car compared to the Grand National.
Exclusivity and Collectibility
Perhaps one of the most significant differences between the Grand National and GNX is their relative rarity and collectible status.
The Buick Grand National, while not a common car, was produced in relatively large numbers. In 1987, its final year of production, Buick manufactured approximately 20,000 Grand Nationals. This made it a sought-after vehicle but still attainable for many enthusiasts.
In stark contrast, the GNX was produced in extremely limited numbers. Buick manufactured only 547 GNX models, all in the 1987 model year. This limited production run, combined with its enhanced performance and unique features, immediately established the GNX as a highly desirable collector’s item.
The exclusivity of the GNX is further emphasized by:
- Each car came with a numbered dash plaque
- Comprehensive documentation including letters from Buick, ASC, and McLaren
- Original window sticker detailing all GNX-specific features
- Special owner’s jacket provided to original buyers
These factors have contributed to the GNX commanding significantly higher prices in the collector car market compared to even well-preserved Grand Nationals.
FAQs About Buick Grand National And GNX
- How much faster was the GNX compared to the Grand National?
The GNX was about 0.8 seconds faster in 0-60 mph acceleration, completing it in 4.7 seconds vs 5.5 seconds for the Grand National. - Were all Grand Nationals and GNXs black?
All 1987 Grand Nationals and GNXs were black, but some earlier Grand National models came in two-tone paint schemes. - How many GNXs were produced compared to Grand Nationals?
Only 547 GNXs were produced, all in 1987, while about 20,000 Grand Nationals were made in the same year. - What makes the GNX more valuable than the Grand National?
The GNX’s limited production, enhanced performance, and special features make it more rare and desirable to collectors. - Could you order a GNX with T-tops like some Grand Nationals?
No, GNXs were not available with T-tops or sunroofs to maintain structural rigidity for improved performance.