1957 Corvette 283/283 Airbox Convertible

In the world of 1957 Corvettes, there are Fuelies and then there are Airboxes. Fuelie, of course, is collector-speak for fuel injection, which was a brand-new and milestone status for 1957 Corvettes. The collector’s term “Airbox” refers to fuel injection plus factory Ram Air, which was a brand-new feature that was meant to pump up the Corvette on the racetrack. Milton Robson’s ’57 convertible is one of a mere 43 Airbox Corvettes built in 1957.

Specifically, engine option code 579E was the very pricey $726.30 racers had to spend if they wanted to compete on the track. Just 43 buyers anted up the big bucks to turn their 1957 Corvettes into potential world-beaters.

Corvette’s 1957 engine lineup provides the necessary perspective to appreciate the storied Airbox. The base, no-extra-cost 283 was the 220-horsepower, 4-barrel engine. Chevrolet offered a pair of very hot—but traditional—dual 4-barrel 283s with 245 and 270 horsepower, respectively. The really big deal for 1957 was the arrival of Ram Jet fuel injection. Chevrolet offered four choices. Both option codes 579A and 579C rated 250 horsepower. Both 579B and 579E rated 283 horsepower. The 283-horsepower 283 is the fabled one-horsepower-per-cubic-inch V8, a milestone in a passenger car engine that Chevrolet highly publicized.

Of the two option codes with 283 horsepower, 579E has tremendous bragging rights over 579B. With 579E, Chevrolet mounted an 8,000-rpm tachometer on the steering column. This tachometer looks very much like a hot rodder’s mount. However, the white gauge is 100% factory original and so rare that only the privileged have seen one. Its location was more driver-friendly than the factory pod in the center of the dash. With 579E, Chevrolet pulled the factory tachometer and placed a Corvette medallion, as seen on the rear deck lid, in the vacated opening.

There’s considerably more to Robson’s Airbox Fuelie than the specially tuned Ram Air 283. Option code 684, called the “Heavy Duty Racing Suspension,” was a necessity for track action. Milton’s fully restored, Venetian Red convertible is one of 51 Corvettes so equipped in 1957. Chevrolet engineers, including Zora Arkus-Duntov, tuned the Corvette for the track with heavier-duty springs and shocks, front and rear. They upped the size of the front stabilizer bar. Nothing less than Positraction would do for the rear differential. A quick-steering adapter reduced turns lock-to-lock from 3.5 to 2.9. And last but not least, Chevrolet fitted each wheel with ceramic metallic brake linings with ventilated finned drums. Extra stopping power is extremely important on the track, even if racers did have to heat up the brakes for them to work best.

The Airbox Fuelie was capable of 0-60 mph times in the “fives.” Quarter-mile speeds eclipsed the magic 100 mph mark with elapsed times in the low 14-second range. These figures are stunning considering the bias ply tires of the 1950s—and the fact that Chevrolet wasn’t building a muscle car for the dragstrip.

To date, Corvette authorities have located 29 Airbox Corvettes, making this particular example very rare indeed.

SCM Analysis


Vehicle:1957 Corvette 283/283 Airbox Convertible
Years Produced:1957
Number Produced:43 RPO 579E (6,339 1957 Corvettes total)
Original List Price:$4,919.47
SCM Valuation:$70,000-$126,000 (Fuel-injected)
Tune Up Cost:$150
Distributor Caps:$19.99
Chassis Number Location:VIN plate on the steering column
Engine Number Location:Pad on front of block below right cylinder head
Club Info:National Corvette Restorers Society
Alternatives:1959-61 Jaguar XK 150 3.4 Roadster, 1954-57 Mercedes-Benz 300SL
Investment Grade:A

This car, Lot 213, sold for $374,000, including buyer’s premium, at the RM Auction at The Milton Robson Estate in Gainesville, GA on Saturday, November 13, 2010.

News that Milt Robson was auctioning most of his collection sent shock waves through the automotive community. Housed in a 26,000-square-foot former horse barn equipped with a working saloon, a vintage barbershop, a diner, and a reproduction Mobil Gas station, Robson’s collection was filled with a variety of cars that were of outstanding quality and pedigree. And each was typically the rarest, highest performance version of a given marque or model.

This 1957 Airbox Corvette is exactly that.

The importance of the Airbox cars can’t be overstated. Remember, the Corvette was very close to being Chevy’s two-seat Edsel. Sales were dismal until the revamped 1956 model, and even then, the Corvette was still on the corporate bubble. The ‘57 Corvette added stunning performance and the mystique of one-horsepower-per-cubic-inch, but it wasn’t until March 1957 that the tide truly turned.

A pair of Airbox cars were entered in the 12 Hours of Sebring, ostensibly by Dick Doane Enterprises of Dundee, IL. But, make no mistake, this was a truly a factory Chevrolet effort. After two years of development by Zora Arkus-Duntov’s engineers, the Corvette finally arrived. One of the team drivers, Swiss émigré Gaston Andrey, told me in a 1990 interview, “It was handling as well as a Ferrari and a Maserati at that time. Perfect balance, and they set it up perfectly. We had excellent competition in the Mercedes 300SL, and we surprised them and we surprised ourselves.”

Winning on battered brakes

Sebring is brutal on brakes, and since they were entered in the GT class, the Corvettes had to use factory components. Even with the optional Cerametallic heavy-duty brake option, the cars had trouble. Andrey’s teammate, Dr. Dick Thompson, told me, “We had our usual brake problems. The only thing that would have solved the problem would have been disc brakes. The brakes would only last about a half hour.”

GM even tried equipping the cars with a crude form of anti-lock braking to improve their performance. Still, both cars performed beautifully despite this issue, and finished 1st and 2nd in class, 22 laps in front of their nearest competitor, a Mercedes 190SL.

Other Airbox Corvettes dominated SCCA B-Production racing that year, with Dr. Dick Thompson earning the National Champion title in that class. Competition proved the ‘57 Corvette, and sales were almost double the 1956 model.

GM enforced a corporate ban on auto racing in 1957. Perhaps that is why Chevrolet did not offer a competition model again until the 1963 Z06, making the Airbox cars unique in C1 lore. But the fuel-injected engines and competition brake and suspension options continued to be offered, and Corvettes dominated racing through the rest of the C1 era. It’s no coincidence that Corvette sales increased for years to come.

Highest auction Airbox price

Milt Robson’s reputation might have been enough to drive the bidding to the estimated $250k-$350k. An array of Bloomington Gold and Top Flight awards, extensive documentation, features in enthusiast magazines, and even 1950s-era photographs of a former owner only reinforced the buzz on this car.

The result? The car sold for $374,000—the highest Airbox auction sale ever (the next highest Airbox was sold in 2006 for $237,600). Considering the rarity of an Airbox auction—and the potential appreciation of these special Corvettes—I’d say both seller and buyer made an outstanding deal

Comments are closed.