1957 Corvette Airbox Car - Factory-Backed And Fully Packed

This '57 "Airbox Car" Was An Open-Track Threat Right Off The Assembly Line

Wayne Ellwood Apr 1, 2008 0 Comment(s)
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Once the body was restored, the first step in rebuilding the car involved the application of a gel coat.

The Husseys' research also turned up a comprehensive file on the car's race history, along with some period photos of the Vette in action. It seems that Mouat raced the car continuously in the B/P class from 1957 until 1964, placing as high as Second overall. Assuming this information is accurate, the Husseys' car could be the one of the most extensively raced Corvettes of the period.

Around 1965, a subsequent owner attempted to return the Vette to streetable condition. After driving the car for a few years, he placed it in storage, where it remained until the Husseys purchased it and returned it to the condition shown here. While it may not hit the track with the same frequency and intensity it once did, it's nice to know that this historically important factory racer is once again being used as its designers intended.

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With that done, the primer was applied.

The First Corvettes Go Racing
The development of the Corvettes that were eventually known as the airbox cars began in February 1956. Ed Cole wanted to develop the Corvette from a touring car into a genuine high-performance vehicle. He hired John Fitch to transform the '56 model into a reliable platform for GM's early road-racing efforts at Sebring.

Development moved quickly, but the Corvettes were too heavy to be effective on stock suspension components. Fitch added an extra leaf to the rear springs, then installed stiffer (340-pound) front springs; 1.375-inch shocks (up from the stock 1.0-inchers); finned brake drums with sintered, cerametallix linings; and airscoops to cool the brakes. He also increased the diameter of the front stabilizer bar from 0.068 to 0.081 inches, reduced the steering ratio, and added a new limited-slip Positraction

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Hood and trunk straps were fitted to the car, as the standard latches weren't reliable on the track. Fitch's group also fabricated what was perhaps the first cold-air intake to deal with high underhood temperatures. In the process, they relocated the generator to the right side of the engine bay to give the tension side a firmer grip on the water pulley. The final addition was a steering-column-mounted tach

By March of 1956, four Corvettes were ready to run at Sebring-three in the Production Class and one in the Modified Class. One of the Production cars finished First in class and Ninth overall. Fitch is quoted as saying, "Our performance was less than we had hoped but more than we deserved." More importantly, this development process yielded what eventually became the components for the RPO 579E and RPO 684 options for '57.

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When the '57 Corvette was introduced in the fall of 1956, it featured the new Rochester fuel-injection system. By April of 1957, a second, more powerful FI system-the airbox option developed by Fitch-was introduced. RPO 579E was actually a collection of small improvements to the original FI setup. The biggest single improvement came from the airbox itself, which was mounted to the driver-side inner fender panel and drew cold air from the left of the radiator.

Inside, the tach was moved from the standard location in the center of the dash to the steering column. The airbox option, which was clearly intended for racing, also included a heater-and-radio delete. Combined with a lack of ignition shielding, this feature permitted a more favorable routing for spark-plug wires. Of the 43 RPO 579E Corvettes built for '57, only 23 are known to exist today.

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Another race-oriented option, RPO 684, was introduced in '57. It featured all the developments from Sebring, including the heavy-duty springs and shocks, the extra leaf in the rear spring, and the finned brake drums with cerametallix linings, vented backing plates, and cooling scoops. Of special note was an air-duct system that ran into the fender wells and through the rocker panels to feed cold air to the rear brakes. This was also the first year for the synchronized four-speed transmission, Positraction differential with three available gear ratios, and 15x5.5-inch wheels. A total of 51 '57 Corvettes were built with the RPO 684 option.

SCCA National Points in B/P Class (East Coast, Northeast Region)
1957 - Third (21 points)
1958 - Second (46 points)
1959 - Sixth (8 points)
1960 - Eleventh (8 points)
1961 - Nineteenth (400 points)
1962 - No information
1963 - Ninth (1,200 points)
1964 - Incomplete season

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