1963 Chevrolet Corvette Z06

The Chevrolet Corvette was brought to market late in 1953, equipped with inadequate brakes, an anemic six-cylinder engine, a two-speed Powerglide combination, and an antiquated suspension and steering system. Its sports car appearance was certainly not backed by performance credentials. This all changed, however, within a few years through the efforts of Zora Duntov, John Fitch, Dick Thompson, Ed Cole, and Frank Burrell.

By selecting the correct boxes on the options list, buyers could receive a solid lifter, fuel-inject V8, four-speed manual transmission, race-tuned suspension, heavy-duty brakes, and a myriad of other performance components. The Corvette could be transformed from a road-going vehicle to a proper track-ready machine straight from the showroom floor. The Fiberglass-bodied Corvette quickly grew into a dominant force in production-based road racing in America as the 1950s progressed, and between 1956 and 1960, Dick Thompson, J.E. Rose, Jim Jeffords, and Bob Johnson scored seven SCCA national titles with the Corvette.

1963 was the only year for the 'split-window' body style of the Chevrolet Corvette and for the first time, 'America's sports car' was available as a Coupe as well as a Roadster. The new 'Stingray' design, credited to Bill Mitchell and Pete Brock, was a true fastback, notable for the unique divided rear window, was praised for its appearance but criticized for its detrimental rearward vision. After just one year, that feature was replaced with a single-piece backlight. The 'C2' platform, as it would later be known, was a major advancement from earlier Corvettes, and it was designed from a clean sheet of paper to be a proper sports car rather than a mere styling exercise. The new Sting Ray Coupe featured 'wind split' indentations on the front fenders behind the wheel openings and ribbed rocker panels, hidden, retractable headlights, and aircraft-type doors that cut deeply into the roof to ease entry and exit. The interior was completely redesigned as well with a more modern look but with a more traditional gauge layout. Beneath the fiberglass shell was a new independent rear axle with transverse leaf springs, control arms, multiple links, double-jointed half-shafts, and trailing radius rods.

The base 327 cubic-inch V8 delivered 250 horsepower while the Rochester fuel-injected, solid-lifter L84 327 cubic-inch version boosted output to 360 bhp. This marked the first time an American production car had a higher horsepower figure than engine displacement. A three-speed manual transmission was standard, but options included a four-speed manual, a Positraction rear end, and a variety of rear axle ratios. The Stingray could be ordered in any of seven exterior colors. High-performance extras also returned from 1962, including metallic brake linings and Positraction, but the big news the Regular Production Option (RPO) Z06 Special Performance Equipment package for the coupe. This special group of options had been selected through extensive testing and racing by Zora Arkus-Duntov, creating an uncompromising factory race car. It allowed Chevrolet to circumvent GM's self-imposed ban on factory-sponsored racing or support, by offering all the performance components as optional equipment.

The Z06 Special Performance Equipment package included the L84 327/360 HP fuel-injected V-8 and heavy-duty Muncie M20 4-speed manual transmission, power brakes with dual circuit master cylinder, metallic brake shoes, backing plate air scoops and heavy-duty suspension. Special heavy duty-springs, shocks and a front sway bar replaced the standard pieces to meet the rigors of high-speed competition. The upgrades to the brakes were perhaps the biggest improvement, mounted on ventilated backing plates fed by rubber 'elephant-ear' scoops, the Z06's large cast-iron finned drums contained oversized, segmented, sintered metallic linings, forward self-adjusters and unique 24-blade internal cooling fans. The entire operation was controlled by a unique dual-circuit Kelsey-Hayes master cylinder and Delco-Moraine vacuum booster controlled the entire operation. A total of 199 examples received the Z06 package and 63 were fitted with the N03 36.5-gallon competition fuel tank with oversized filler cap and neck for quick pit stops perfect for longer race tracks like Daytona or Sebring. Cars equipped with the larger fuel tanks were known as the 'big tank' and this option was dropped in December of 1962 in order to make the Z06 package available in convertibles, which could not accept it. The knock-off wheels were abruptly canceled when it was discovered that early production units leaked air.

The Z06 Package complimented the styling and handling of the all-new Corvette, offering an impressive performance intended for the racing circuit. With a price of $1,818.45, the Z06 package added nearly half the base price to the Corvette, but for the hardcore racer, it was worth every penny.

by Daniel Vaughan | Aug 2007