Star and (Black) Stripes, Duntov's fabled Grand Sport Corvette finally lays rubber in Europe

Source:  AutoWeek Magazine
(12:00 July 24, 2000)

Star and (Black) Stripes, Duntov's fabled Grand Sport finally lays rubber in Europe


It's crowding middle age, but this surly slab of American muscle can still power-lift its front wheels off the road or paint black stripes on it with its Blue Streaks for as long as it pleases. It has kept its waistline close to its original trim ton, packs a rowdy 600 horses in its aluminum small-block, and only a man named Armstrong is allowed to handle it. It's a Grand Sport Corvette, and it's notorious--Chevrolet's Bad Seed.

So Bad that fusty old General Motors tried to kill the car at birth. In 1962, company maverick Zora Arkus-Duntov, concerned about the upstart Ford-powered Shelby Cobras, planned to homologate 100 of these lightweight race versions of the new Euro-style, but all-American, Corvette coupe for international GT racing. He even had Le Mans in mind, but managed to finish only five prototype Grand Sports before word came down early in 1963: We thought we told you we're not in racing.

Duntov had to back off, but he made quiet arrangements to have the five survive in private hands, and last month a latter-day GM with a vastly different world view (and finally with a Le Mans under its belt) was proud to have one at the Goodwood Festival of Speed to show What Might Have Been.

"We're encouraged that GM is taking interest in their heritage," commented owner-driver Tom Armstrong. "I live this heritage. Corvettes are my favorite cars. We must have five or six in the family at any one time."

Having cashed out of a paperboard packaging business, Armstrong and his wife, Susan, are now full-time vintage racers based near Seattle. They have several other competition machines, including an ex-Mark Donohue Camaro, a Ford GT40, a D-type Jaguar and a Can-Am Lola T162, as well as Mrs. Armstrong's own racer, a '63 split-window. But this Grand Sport is the glory of the stable. Chassis No. 003, it was originally raced by the likes of Roger Penske, Jim Hall and A.J. Foyt at places like Sebring and Nassau.

Armstrong has been its custodian since 1989, running it half a dozen times a season. This was his second invitation to Goodwood; he believes that when he came to the hillclimb in 1997, it was the first time any of the Grand Sports had been in Europe.

The couple were surprised to find their bad-boy's fame had preceded it.

"I was amazed how enthusiastic the fans are, and how knowledgeable," notes Susan. "One little boy came, and he has a model of this car. Everybody loves it."

So does Tom. "The car is a handful," he grins. "It's marvelous to drive, but it follows the old line, `Know where you want to be before you punch it, because you're gonna be there shortly.' It's so light and has so much power, it will break loose at almost any point. Or when the rear end hooks up in first or second gear, like out of the last turn at Sears Point, the front tires will come up several inches.

"I didn't try to do any of that at Goodwood, but I'm not used to standing starts, and the clutch is so sudden that just immediately I was spinning the tires. It was wanting to burn rubber in all the gears all the way up the hill."

Though the Grand Sport looks a lot like a standard C2 Corvette, it's much more than a hot-rodded street car. Duntov was so determined to save weight and boost performance that virtually every component was remade. According to Armstrong, "The steering wheel, the wipers and the shifter are the only production parts. All the rest is special fabrication. Even the door latches are hollow." Heavy dieting resulted in a vehicle weight of less than 2000 pounds, two-thirds the heft of a normal C2.

Crammed inside the look-alike GRP (glass-reinforced plastic) skin, which itself is abnormally thin, is a cockpit-bracing "birdcage" remade in aluminum, rather than the standard steel.

The ladder-type chassis frame is steel, as in the production version, but here it's six-inch, round-section tubing. Suspension is similar in layout to the street car's, but the hardware is custom-built. From its debut, the GS had the disc brakes that would not be on the street C2 until the 1965 model year.

It also had an engine that would never be produced--more than one such, actually. Chevrolet engineers were busily exploring aluminum block and head technology, and Duntov seized the opportunity to revive the big-valve hemispherical combustion chambers he'd pioneered on his old Ardun conversions for flathead Fords. With dual spark plugs to assure ignition, a prototype displaced 377 cubic inches and produced 550 hp, stunning numbers for the day. (Armstrong has one of two survivors, but considers it too valuable and fragile to run.)

Due to the management clampdown, the 16-plug engine was never raced, so Grand Sports got various less-exotic powerplants, though some were all-aluminum 377s making 485 horsepower. There were other installations, too; according to owner Armstrong, later in the 003's career it was the first Corvette to race with a 427, at Sebring in 1965.

Today, Armstrong has kept the faith by installing a modern aluminum small-block stroked to 402 cid under a period-correct quartet of 58-mm twin-barrel, side-draft Webers. He quotes a peak horsepower of 600, and 600 lb-ft of torque. Enough to keep the old beast truculent, he reports.

"Driving it, you have a lot of noise and there's a thrilling sensation of speed and acceleration. This car really gets things done between the corners.

"The car is so tall it's a brick at speed, and at high speed the handling gets real light. GM built several hoods to reduce front lift, and this is `the Sebring hood' I've got on, with the most venting, but it still catches all kinds of air under there.

"The brakes are good, as long as you know it might do a wiggle on you and you're ready for it each time, and you've picked your nice, smooth place, and you don't jump on the brakes. And if you've done a good job of warming them up. These brakes need warming up.

"Turning in, it might jitterbug a little getting that bite. But once it takes its set it's very dependable. You can play sprint car real easy, it's a lot of fun. But you don't want to do something sudden and disturb it. Sometimes I've gotten in a hurry, trying to get a jump out of a corner on somebody, and thrown the power down too hard and all hell breaks loose. The ass end comes out, and you just don't go anywhere.

"On the backstraight at Portland, which has that little bend in it, unfortunately you have to grab fourth gear right in the middle of that bend. You better have planned for it, 'cause the back end comes out two or three feet."

Armstrong adds that his experience with this historic machine gives him new respect for the drivers of its day. "When I see those old films, I can't believe how they're honking those cars around. They're just manhandling them, and they're using all of the road, and there's a little bit of rubbin' going on. The cars looked pretty used when they came in. In vintage racing, you know, any contact is a no-no."

As often is the case in the vintage racing ranks, this is an owner who first wanted his old car when it was new. In Tom's case, he enjoyed the enthusiastic support of his racer-wife. "I never saw the Grand Sport race originally, but I saw the magazine articles on it, and it was a dream to me. The day the former owner, Bob Paterson, told me he wanted to sell it, I called Susan over and her answer was, `Oh goody!' "

And how has ownership turned out? "I'd say it doesn't take a lot to maintain the car. It wears out brake rotors fast, so we have to have new ones made, and of course it's tough on halfshafts and drivelines because it's putting so much power down. I had a halfshaft break once and that damaged a rear upright. That's the only really difficult challenge I've had. I could have just put a regular production-car piece on, but I didn't want it on there, so I had [the original] patterned and cast, completely duplicated. I had five built, incidentally--I've got one for each of the other Grand Sports."

Like most vintage owners, Armstrong takes great pains to maintain originality, providing it doesn't compromise his racing the car. Its gray-blue paintwork is a precise rendering of former owner John Mecom's team color as used at Sebring in '64, said to be a Cadillac hue from the '50s, and markings and decals have been reproduced as exactly as possible. However, Armstrong rebuilt the front suspension arms with heavier-gauge materials, because "some original parts were so light they just sagged." That, plus the addition of a stronger roll-cage structure and a dry sump system added an estimated 100 pounds.

Tires are period-correct bias-ply Blue Streak Sports Car Specials manufactured by a Goodyear plant in Chile. The Grand Sport chews them up in about six vintage race days.

As much as he loves this old brute, and admires the industrial and humanistic drives that brought it to be, Armstrong acknowledges that the GS program was not a success. "No, it was not. Chevrolet pulled out, so the cars went privateer racing without all the factory parts. And they couldn't run as production cars. They had to run in sports classes, and they were outclassed there by the new rear-engine cars coming on in 1964 and 1965."

Still, the Grand Sport has meaning. Though not the first American-made challenger to European cars, it was among the first, and certainly one of the most all-American. It's rich in technology and craftsmanship and savvy. It's also rude, crude and lewd, not to mention loud, with all the suave style of a biker gang sporting Stars-and-Stripes tattoos.

What a damn shame Zora never got it to Le Mans.