Zora Arkus-Duntov, commonly refereed
to as the father of the Corvette, was tasked creating the SR-2. He worked with Chevrolet's Chief Engineer, Ed Cole, on creating
a version of the Corvette that could outrun and outpace the competition.
A modified single-seater Corvette test-bed was brought to
the Daytona Speedweeks in February of 1956. Its V8 engine produced around 240 horsepower and carried the car to an average
speed of 150.58 mph. A little more fine-tuning to the engine increased the horsepower to 255. The car traveled the smooth
sand surface at an average speed of 147.3 mph which was nearly 15 mph faster than the Ford Thunderbird's run.
The
first cars to bear the SR name were shown at the 12 Hours of Sebring in 1956. It is still a mystery as to the official meaning
of 'SR'; some believe its for 'Special Racing', others say its for 'Sebring Racer', while others argue its just initials.
Four 'SR' cars were entered in the race, three with a 265 cubic-inch engine and one with a 307 cubic-inch unit. The 307 ci
car had a newly created, and still unproven, Rochester mechanical fuel-injection system and a ZF close-ratio four-speed gearbox.
It raced in the Class B category while the three other cars competed in the Class C group.
One Class C and the Class
B entry retired prematurely from the race. John Fitch drove one of hte Class C cars to a very respectable 15th place finish.
The other entry finished next to last. The Corvette's were still in their infancy of racing but the potential for greatness
had been proven.
From there evolved the SR-2, with inspiration from Harley Earl's son, Jerry, who was head of GM styling
at the time and an automotive sports car enthusiast. Construction of the SR-2 models began with a chassis very similar to
the Sebring cars. The body was designed by Robert Cumberford, a GM designer at the time, and Tony Lapine using design cues
and inspiration from the legendary Jaguar D-Type. The windshield panels were similar to the Sebring cars; a large fin was
placed in the rear and original the cars were without a headrest which was added later in the design process.
Duntov
handled some of the mechanical aspects of the car including the engine. It was similar to the Sebring cars.
Though
intended for racing, it retained many of the refinements of a traditional road going car. It had a wood-rimmed steering wheel,
radio, instrumentation, and even stainless steel decorative panels. This extra weight proved to be its Achilles heal when
it went racing for the first time at Elkhart Lake in June of 1956. After the race, the weight was reduced. The vinyl seats
were removed and replaced with lightweight Porsche Spyder seats. Non-essential components were also removed where necessary
and possible.
There were a total of three SR-2 cars that would eventually be built. The second SR-2 was constructed
for Bill Mitchell. Smokey Yunick prepared the engine and worked on the braking aspects of the car. Having learned valuable
lessons from the first car, the second SR-2 was given lightweight materials which brought its weight down to 2300 pounds.
The average stock Corvette weighed around 3,000 pounds at the time, so the decrease on the second SR-2 was rather substantial.
The Smokey Yunick tuning and weight reduction worked, and the car ran a 152.886 mph at the Daytona Speedweek in 1957.
The final SR-2 was built for GM president Harlow Curtice. This car was destined for the show circuit, and as such,
did not feature many of the exotic setups as the second car. Instead, it had a bolt-on, bolt-off removable stainless steel
top. There were Dayton wire wheels mounted on all four corners and the interior featured many stock Corvette pieces.
The
lessons learned on the Sebring cars and fine-tuned on the SR-2 cars would quickly make their way into the production Corvettes.
One of the first to make its way into the 1957 Corvettes was the four-speed gearbox and the fuel-injection system.
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