Road Test: Guldstrand Nassau Corvette

A supercharged roadster from thunder alley

Jeff BartlettwritersScott Killeenphotographers

Sports-car enthusiasts with a bit of red, white, and blue flowing through their veins speak the name "Grand Sport" with a reverence usually reserved for a religious deity or a person's first love. These five special lightweight road-race Corvettes were factory built in 1963 during a tense dry spell in corporate race involvement. American car companies basically had assumed the role of spectators of international motorsports in the late '50s due to a so-called ban of factory-sponsored racing by the Automobile Manufacturers Association, allowing Ferraris, Porsches, and Maseratis to capture the glory of race victories relatively unchallenged by American machines.

Despite the fact that several car companies were unofficially supplying racing teams with parts snuck out the back doors, it was an outspoken Texan, Carroll Shelby, who challenged the edict by shoehorning a Ford V-8 engine between the fenders of the small English AC roadster in 1962.

The following summer, Corvette chief engineer Zora Arkus-Duntov began work on a series of purpose-built racers to be known as Grand Sports. Although the original plan was to construct 125 of the lightweight cars, GM execs killed the program after only five had been completed.

Big horsepower from a 377-cubic-inch V-8, massive weight reduction, and serious suspension magic were the key components of the Grand Sports. While all five were built as coupes, the tops were cut off two of them to lower the center of gravity and to further reduce weight, a principle proven by Dick Guldstrand in his efforts campaigning a Sting Ray roadster. The drivers of these cars-Roger Penske, A.J. Foyt, Jim Hall, Dr. Dick Thompson, and Guldstrand-became household names, but without the cubic dollars of factory support, they failed to capture the glory envisioned by Arkus-Duntov.

In the years that followed, Guldstrand continued his tight relationship with Chevrolet by racing Corvettes and contributing greatly to the suspension engineering of the production cars. All the while, his company on the famous Thunder Alley in Culver City, California, was using lessons learned on the track to benefit street Corvettes. In the late '80s, Guldstrand produced a tuner car of his own, the Traco-powered 5.7-liter Corvette GS80.

With the introduction of the Corvette ZR-1, Guldstrand was set on building a Grand Sport of the '90s: a '60s-flavored, high-performance car with a modern level of safety, comfort, and power. With the design talents of Steve Winter, a special body was molded from composite carbon fiber to give the GS90 an attractive, distinct appearance, which hides serious engine and suspension modifications.

At the International Nassau Speedweeks in 1963, the Grand Sport defeated Shelby's Cobra. Now, more than 30 years later, this memorable venue has served as inspiration for a new series of roadsters, the Nassau, being hand built at Guldstrand Automobiles (GSA). Based on LT1- or LT4-powered '90-to-present Corvette convertibles, the Nassau offers the same swoopy design as the GS90 in a more budget-friendly package. Naturally, changes were necessary to adapt the GS90 profile to the standard-body Corvette, but the same beautiful lines remain intact.

Fastened mostly on existing mounting points, the composite carbon-fiber body contributes to the slight weight savings without sacrificing strength and rigidity. By shortening the overall length by six inches and widening the rear by four inches, the impressive Nassau body creates a powerful presence. Only the original hard tonneau cover is left intact; all other body pieces are modified-even the flat rear deck, which is treated to a fresh fuel-filler door. All sculpted air inlets are functional, allowing the venting of warm air and the intake of cool. The front end is kept clean with integrated projector beam headlamps and dual-purpose directional signal/parking lights. The rear features the most daring and nostalgic styling of all: 12 distinct taillights hark back to the original Grand Sports, which had 12 holes cut into the rear panel for lights, airflow, and weight savings.

A specially designed Flowmaster twin-pipe cat-back system vents exhaust gases through two inline resonators, exiting out a center-mounted dual tip. But the real performance gain comes from an optional Vortech supercharger package that boosts output of an LT1 from 300 to 420 horsepower. Consisting of an MSD ignition, K&N filtercharger, and 8-psi Vortech Gearcharger, the package significantly enhances the 5.7-liter engine's performance.

As with all the cars he's built, Guldstrand has focused on the man/machine interface. "You have to keep the car balanced. It all goes back to the guy behind the wheel and what he's capable of doing," Guldstrand said. Since his design work served as the foundation for the '84-present Corvette suspension, Guldstrand is sufficiently qualified to elevate the chassis' performance. The suspension was modified to improve roll centers and add anti-squat to compensate for the increased power. To accomplish this, the tall stock bushings on the front fiberglass leaf springs were replaced with polyurethane wedges, dropping front ride height by 0.75 inch. The rear suspension was dropped an inch by using new bolts and polyurethane bushings, without altering the original geometry. Further improving road handling is a set of massive Pirelli PZero Asimmetrico tires (front 295/35ZR18, rear 335/30ZR18) wrapped around 18-inch three-piece O.Z. Italy wheels. To handle the kind of hard driving this car encourages, the factory heavy-duty disc brakes were dimpled and channeled to help vent brake pad gases and reduce heat. Guldstrand chose to avoid cross-drilling because of typical problems with rotor cracking under hard usage.

To enter the car, a microswitch hidden in the molded door handles must be triggered by hand or via a key fob, which then activates the electric lock/unlock mechanism. The interior is familiar Corvette fare, with high sills, a digital speedometer amid analog gauges, and hip-hugging leather seats. An engraved plaque beside the shifter indicates the production number and authenticity of the vehicle. In our case, we were in command of Nassau #001 completed only the day previous for an eager customer.

A turn of the key ignited the fuel-injected V-8, signaled by a throaty exhaust that warns bystanders that beneath the soft edges lurks one bad-ass car. A faint supercharger whine indicates that this special Corvette has more to offer than meets the eye.

Heading north to open canyon roads, where the Nassau could be flogged without scaring the neighborhood, the ride quality was surprisingly compliant. No apologies were needed for the low-profile tires or the lowering.

With shifting duties handled by the four-speed automatic, we were able to focus on negotiating the twisty hillside turns with both hands on the wheel.

Making our way around decreasing- radius turns, sneering at switchbacks, and gobbling up straightaways, we became comfortable with the Nassau's impressive limits. The balance and tightness of the car inspired confidence that would permit indulgence in tail-happy oversteer without drama.

Fresh from driving a '96 LT4-powered Corvette convertible, we found the Guldstrand to be a more predictable car that would encourage mischief and offer forgiveness for slight misjudgments.

Of the numerous modifications to this Corvette, the suspension stands out as offering the most significant improvement for the money. The fine-tuned balance created by the Guldstrand setup immeasurably heightened the driving experience, providing a precise on-center feel with poised turn-in. Around challenging turns, the Nassau permits the driver to be an active participant in the vehicle's dynamics and not just react to them.

When commanded, the power delivery began strong and grew Herculean as the tach needle rose. The supercharger barely could be heard over the gruff exhaust at idle, and it was muffled completely by the engine's war cry at full throttle.

From low speeds, the Nassau out-accelerates the stock Vette like a hell-bent ZR-1. The combination of the politically incorrect 3.73:1 rearend, superfat Pirelli tires, and 8-psi supercharger provides a one-of-a-kind thrill ride destined to leave the driver grinning like the Cheshire cat. Based on output numbers, gearing, and our seat-of-the-pants impressions, we estimate 0-60-mph times to blow past the ZR-1 in the mid-fours.

We were reminded of the Nassau's striking appearance by countless gawking motorists during our ride, many of whom rolled down their windows to shout inquiries: "What is it?" and "How much?" Beyond the breath-taking exterior design, GSA offers customers the opportunity to equip the vehicle with the balance of suspension and engine tuning to match their needs. As it sits, the basic Nassau package adds $35,000 to the price of the donor convertible, with the power-boosting supercharger costing another $5000.

While the Nassau commands a premium price, its labor-intensive construction is awe-inspiring in its attention to detail and quality. Few domestic tuner cars (the Saleen Mustang SR351, Lingenfelter 383 Corvette, and Hennessey Venom Viper) hover in this price stratosphere, making the Nassau an attractive low-volume collectible in rare company. For the average Corvette enthusiast, the Vortech setup is the best place to start, with the Guldstrand suspension being a desirable second stage.

Guldstrand summed up the essence of the Nassau: "It's an American car. That's what it's about. It's an American car that [the customer] is very proud of, and you know, it kicks butt."

For more information, contact: Guldstrand Automobiles, 11924 W. Jefferson Blvd., Dept. MT, Culver City, CA 90230; 310/265-0063.

Guldstrand Nassau
Body style 2-door, 2-passenger
Vehicle configuration Front engine, rear drive
Engine configuration Supercharged V-8, OHV,
2 valves/cylinder
Engine displacement, ci/cc 350/5737
hp @ rpm, SAE net 420 @ 5200
lb-ft @ rpm, SAE net 429 @ 4400
Transmission 4-speed auto.
Axle ratio 3.73:1
Wheelbase, in./mm 96.2/2443
Length, in./mm 172.0/4369
Width, in./mm. 75.0/1905
Base curb weight, lb 3300 (est. )
Fuel capacity, gal 20.0
Suspension, f/r Control arms/multilink
Steering Rack and pinion, power assist
Brakes, f/r Vented discs/vented discs, ABS
Wheels 18 x 10.0/18 x 12.0,
three-piece aluminum alloy
Tires Pirelli PZero Asimmetrico,
Base price $81,000
Price as tested $86,000
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