First of a Series of Five Pilot Competition Test-Fleet Corvettes Before the 'Airbox' Corvette, Five Fuel Injection Corvettes with Heavy Duty Brakes and Suspension, and 4-speed transmissions were assembled at the St. Louis GM plant in February of '57. Zora's specially built 'Field Test Fleet' Offered for sale is an impressive example of an ultra-rare 1957 Corvette originally assembled with Fuel Injection (RPO-579C), Heavy Duty Brakes and Suspension (RPO-684) and T-10 four-speed (RPO-685). This Corvette (2276) includes rear leaf-springs with engineering part numbers not yet available on GM's part list which add to the mounting proof that this Corvette was part of Zora's special 'Competition Test-Fleet.' During this time, GM's engineering department was busy pushing build orders at warp speed. Just before, in 1956, Zora Arkus-Duntov and crew readied the Corvette Super Sport for debut at the New York Auto Show in December. Chevrolet's first purpose built race car was slated to run at Sebring in 1957. Many of the parts designed to go on the SS needed testing and trusted racers to return feedback on their performance. In order to do so, not only did GM need to design, manufacture and procure the parts necessary, they needed to fit them to 'Test Fleet' Corvettes. The rear leaf springs, an engineering 0 dash part number, was fitted to this Corvette in St. Louis before becoming available to the public. How these Corvettes, and their engineering parts, ended up in the hands of GM friends and racers, is somewhat unclear. Mack Yates, racer and co-owner of Barford Chevrolet of Clayton, Missouri (one mile from the St. Louis plant), ordered the second Competition Test-Fleet Corvette #2281. Yates' Corvette included fuel injection, HD brakes, and a four-speed which was SCCA raced from '57-'59. As one of the largest new Corvette dealers in the U.S., Barford Chevrolet's close proximity to GM's St. Louis plant, and special-order service specializing in high performance, shed light on Zora's goal for real-world performance testing and feedback. Ken Kayser, a well respected researcher and author with access to Zora's personal engineering files, verifies this 'small 'Pilot' run of eight to twelve 'Competition Corvettes'' in St. Louis. He states in his book Legend or Myth Zora's Marque of Excellence Volume III - The History of Zora's 'Ramjet' Fuel Injection, The 'Competition Corvette Pilot Run' with VINs in the E57S102030 to S102325 range incorporated the following RPOs: RPO-684 HD Brakes Suspension RPO-685 Borg-Warner T-10 four-speed RPO-677, 678 679 Positraction with 3.70, 4.11 4.56 axel ratios RPO-276 Kelsey-Hayes Co. 15x5.5' Steel Wheels 3748348 RPO-469C 270 HP V8 possibly including the 8,000 RPM AC 1548680 Tachometer Upgrades to the RPO-579C 283 HP V8 including the 8,000 RPM AC 1548680 Tachometer This 'Field Test Fleet' was assembled prior to availability of Corvette bodies with rocker panel ducting to the rear wheels. Most of Zora's Field Test Corvettes were originally painted Polo White with a red interior. Mike Hunt, originator of Research Project 1956/1957 , had what appeared to be unprecedented access to information relating to Corvettes assembled in St. Louis. Hunt 'maintained for thirty years that Chevrolet St. Louis assembled two RPO-579C Fuel Injected Corvettes for conversion in to fresh Sebring Racers, in the VIN range S102000 to S102200.' Internal GM Engineering Build Orders surfaced verifying the activity relating to the Sebring race in '57. One build order in-particular, dated January 14, 1957, requests competition brakes for Sebring Race. Mike Hunt's letter to Rich Mason mentions, 'prior to the airbox, there had to be some H.D. non-airbox cars. Chevrolet was competition developing 1956s, so 1957 was just a continuation.' Hunt also states, 'they almost definitely built some 'special' or 'slightly special' cars. Some were probably sold via normal channels some were probably done for Chevrolet people and/or their favorite competition
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