Driving the Superformance Corvette Grand Sport

Cook’s Corner opened in 1926, serving the good stuff after Prohibition. Today the rugged roadhouse is one of Southern California’s most famous biker bars. Tucked away in Aliso Canyon, its weathered wood façade and rural setting feel a world away from L.A.’s urban sprawl, although the clog of two freeways and the endless restaurant chains and housing developments of Irvine lurk just a few miles to the west.

On the weekends this place is packed with hundreds of bikers looking to escape real life, but on this late Wednesday afternoon, we find a dozen Harleys sitting in the sun. Their owners are shooting pool and shooting the breeze, enjoying some onion rings and a few cold ones.

When our side pipes sing, the place empties out. We’re driving a Superformance Corvette Grand Sport, and the rumble from its 550-horsepower LS3 is a siren call few can resist. “We could hear you coming down the road going through the gears,” one guy tells us. “You were shaking the sawdust on the floor,” he says with approval. “It sounds fantastic.” The big, all-aluminum V-8 even idles nasty at 1100 rpm, rocking the car like a busted Maytag dryer.

Superformance is an outfit best known for its Cobra and Cobra Daytona replicas, selling about 350 cars worldwide last year. But about four years ago, the small-volume manufacturer, which is based in South Africa, began building Corvettes.

And not just any Corvettes, faithful recreations of the car many say was Zora Arkus-Duntov’s masterpiece, the 1963 Corvette Grand Sport. Duntov planned to build 125 of the lightweight and specially prepared Stingray coupes to barrage the international racing scene, aiming to kick Shelby’s Cobras right in the fangs and Enzo right where he lived. But GM officially pulled out of racing that year, leaving Duntov with just five completed cars which he gave to privateer teams, including Roger Penske, Dick Guldstrand and Dr. Dick Thompson (“The Flying Dentist”). Today those five cars are in private collections and seldom see sunlight. They represent the holy grail of Corvettes. In 2009, Grand Sport #002 sold for a rumored $5,000,000.

Back at Cook’s Corner, it’s a party around the Corvette. Phones are out and selfies are being taken with the car. We unbuckle the two leather straps that secure the hood and reveal the heart of the beast. There’s a collective gasp. Lingenfelter Performance Engineering in Decatur, Indiana, supplied the 6.2-liter V-8 with an 11.5:1 compression ratio, severe camshaft, ported and polished CNC heads and Borla eight-stack fuel injection. It’s beautifully finished, to say the least.

One guy knows what he’s looking at. “Wow, it’s got air conditioning,” he says pointing to the compressor and the serpentine belt. “It does,” we tell him. “Vintage air, and it blows hard and ice cold. It was freezing us out. Power windows too. But no radio.”

Another guy chimes in. “Why bother? You couldn’t hear it anyway over those massive sidepipes.”

And that’s a fact. On the highway at 80 mph, the Tremec T-56 Magnum six-speed manual transmission has the V-8 turning only 2300 rpm, but it still sounds like the small-block is churning inside the cabin alongside you. The engine’s roar combines with quite a bit of road noise from the car’s massive tires. The Grand Sport is nonetheless comfortable enough to be driven cross-country, provided you pack some ear plugs. In fact, Superformance principle Lance Stander and his son just drove the car on a 3400-mile road trip all over the West, from L.A. through Colorado, Utah, and back, meeting up with Superformance owners along the way.

“I’ve been a Grand Sport stalker for over 20 years,” says Stander, sitting in his office at Hillbank, the company’s American retailer located in Irvine, California. “I’m actually a Chevy fan that came to America from South Africa in 1998 and started selling Fords. But I’ve always wanted to make Grand Sports,” he says with a smile. “The first time I actually saw a real Corvette Grand Sport was only about 14 years ago in Monterey, but I owned a 1963 Corvette convertible in South Africa when I was 25 years old.”

Getting into the Corvette business wasn’t easy. It took eight years to secure the license from General Motors to build these Corvettes, and today Superformance builds the cars in partnership Duntov Motor Company in Farmers Branch, Texas. “They build race cars, and we build the street cars,” says Stander. Aside from GM, they are the only companies in the world that can legally make Corvettes that wear Corvette logos. So far Superformance has built 26 Grand Sports.

Stander purchased the original Grand Sport chassis tooling, blueprints, jigs and fixtures along with an original Grand Sport body from Robert Ash of Racing Icons. Ash is the Grand Sport guru, with experience restoring three of the original five Grand Sports.

This has allowed Superformance to build tube chassis and composite bodies extremely similar to Zora’s original designs, with a few key modifications for strength and drivability. The chassis uses four-inch steel tubing just like the original, and the dimensions are the same, but Superformance adds rack and pinion steering, stiffer rubber and polyurethane bushings, front coilovers and Bilstein shocks. The rear end is pure mid-year Corvette, right down to the transverse leaf spring and limited-slip differential. The body is made of hand-laminated fiberglass and is just like the original except for double door seals for better weather and sound insulation.

Just like the Cobras and other models it produces, Superformance builds its Corvette Grand Sport in South Africa and then ships them to Hillbank as rollers. It’s up to the buyer to have the engine, transmission, and driveshaft of choice installed, but Stander can put you in touch with someone reliable. The cars are set up for any Chevy engine (original small-block, LS, LT4 or big-block) and any transmission will fit, including an old-school four-speed, a five-speed, a six-speed or even a new eight-speed automatic. Stander says the blue and white example we’re wheeling weighs about 2800 pounds.

Our car sits on massive aluminum wheels made by American Racing. They measure 17×8 inches in front and 18×11 inches in the rear, wearing super sticky Nitto NT555 G2 front tires sized 255/50ZR17 and Nitto Extreme Drag rears measuring 305/40R18. Stander says 75 percent of buyers go for the other option: real 15-inch magnesium wheels that look like the classic Halibrands and Avon tires. We would too.

Paint quality and body fit are excellent and the driver’s door—which feels like it weighs practically nothing—closes with a solid thud. The engine disturbs the peace on the first crank. The hydraulic clutch is lighter than you might expect and the cold steel of the shifter feels good on your palm as you push it up and click into first gear. The throttle is mounted high and its travel is long. This takes some getting used to. Visibility is excellent. Old cars have thin pillars. And you can see the differential cooler (it’s only functional if the owner requests) through the distortion of the plexiglass rear window in your rearview mirror. It’s exactly the same rear view enjoyed by Roger Penske when he drove Grand Sport #005 at Nassau Speedweek in the Bahamas in 1964.

Out on the road, the Corvette’s ride is comfortable enough (probably even better on the 15-inch Avons) and the chassis feels stiff, but there are a few squeaks and rattles in the interior. There are also three-point seatbelts mounted to a four-point roll cage and a sizable trunk that’s carpeted. The high-back bucket seats have enough support but we would choose the old-school low-back buckets which better mimic the interior of the original race cars. Each side pipe is fitted with a catalytic converter so you don’t get blasted with unburned hydrocarbons with the windows open.

Run it hard through the gears and Grand Sport sounds like Dale Earnhardt’s Goodwrench Chevrolet charging toward turn 1 at Sears Point. There’s no redline on the Grand Sport’s 10,000-rpm tach, so we’re upshifting at 6000 rpm, although the engine certainly has more to give. There’s torque everywhere, but the V-8 feels best above 3500 rpm. Cruising Interstate 5 through Costa Mesa, we downshift to fourth and jump on it a few times to roar past civilians in Priuses and other pods.

It’s quick, but the explosive acceleration we were expecting never comes. It’s got more bark than bite. Maybe a stiffer rear gear would help. On a tight mountain road not far from Cook’s Corner the car feels small and light, partially because the steering is over-boosted but also because the car is small and light. Mid-year Corvettes are only 175.4 inches long. That’s shorter than a new Honda Civic.

Zora knew what he was doing. The big V-8 sits well back in the chassis behind the front axle point, so the balance is just about 50/50. There’s very little body roll and mid-corner bumps don’t upset your line. The drilled 12-inch Wilwood rotors and four-piston calipers have enough stopping power, but the pedal play should be more immediate. Also, the tubular frame rail runs right through the center of the driver’s floorboard, and the hump makes left-foot braking difficult. The steering is also a bit abrupt off center, although the ratio is spot on.

The grip is there, but this is not the kind of car you jump in and firewall. It’s the kind of car you creep up on. You have to learn it. Make friends with it. The speed comes as you and the car get acquainted.

It ain’t cheap, either. Base price for a Grand Sport roller is $114,900; $136,895 with options including the Touring leather interior, power windows and a/c; $15,500 for the Lingenfelter engine; $10,500 for the Borla fuel injection; $3,495 for the T-56 Magnum; and $10,500 to install the drivetrain. Total for this example—$176,890. No denying that’s a hefty sum, but outside of the real thing these continuation Corvette Grand Sports are the closest you can get. And maybe that look and that sound are worth it.

We head back to Cook’s to mull it over and, filled with the joy of a very special Corvette, I’m happy to buy the first round.