ZORA ARKUS-DUNTOV'S MULE

test engine at Chevrolet Engineering where it achieved 240 hp at 6000 rpm. The car was shipped to GM’s Desert Proving Grounds in Mesa, Arizona where Duntov drove it to just over 156 mph. He had reached his goal and was now ready to attempt the record run under NASCAR supervision at Daytona Beach. Duntov’s cam earned lasting notoriety as the “Duntov cam” by helping the car blast off to a record 163 miles per hour, an astounding figure in 1955. That same engine was later installed in another famous Corvette, 6901, which set a new record at Daytona of 150.583 mph. Smokey Yunick passed away in 2001. His widow called Smokey’s old friend Steve Tate to come to Daytona, saying that she had “some stuff around the shop” and he should see if there was anything he wanted. That was when Steve discovered an engine marked “Record Run”- the very engine Smokey had installed in EX87/5951 46 years earlier.

After an extensive search Tate discovered the car itself, and purchased it along with its original Chevrolet experimental log book. Working in concert with a small cadre of close friends, Tate then began an enormous year-long restoration project, returning the record-setting engine to its first home and bringing the car back to its original configuration as Zora’s famous test bed and the world’s first high-performance Corvette. Upon its completion EX87/5951 was featured at the 2003 Bloomington Gold Corvette show. An incredible piece of Corvette history, EX87/5951 is the forebear of all the great Corvettes that have followed in its path.

 

EX87 Highlights:
- The original EX87 Arizona Proving Grounds record car, 163 mph
- Original engine installed by Smokey Yunick in 1954
- First Corvette to run the famous “Duntov cam”.
- Purchased from the Bible Broadcasting Company
- Restored to its original configuration as prepared by Duntov
- The first true high-performance Corvette in history

 

Zora assembled a three-car team for the run at a speed record at Daytona Beach, Duntov drove his ’55 mule Corvette dressed with ’56 body panels, while Betty Skelton and John Fitch drove the specially prepared 265ci V8 ’56 Corvettes. All three drivers achieved great success. Duntov had the fastest modified sports car in the standing-mile averaging just under 90 mph. A strong head-wind caused Duntov to fall just short of his previous two-way record, although he did hit 156 mph on one of his runs. For the top speed part of the event, Fitch came in 1st place in the production-sports car class with a speed of 145.543 MPH and Betty came in 2nd place with a speed of 137.773 MPH.  . It should be noted that there were very strong head winds that kept the Corvettes from running over 150-MPH.

Zora didn’t conceive of the Corvette. He didn’t shepherd it from concept to production. He didn’t drive one to a championship. He didn’t have much to do with its styling. Yet Zora Arkus-Duntov is, inarguably, the most important person in the history of Chevrolet’s fiberglass-bodied sports car, so it’s only fitting that Bloomington Gold induct him into their Great Hall next year. Born in Belgium in 1909, Duntov began racing motorcycles and cars when he was 18 and parlayed that interest into a degree in mechanical engineering from the Institute of Charlottenberg in Berlin. He, his wife, and brother fled Europe in 1939, settling in New York, where he and his brother engineered and produced the Ardun hemispherical overhead-valve cylinder heads for the flathead Ford V-8. As legendary as the Ardun heads became, he and his brother couldn’t sell enough to remain in business, so in 1950 Duntov went to work for Sydney Allard, both to assist in producing Allard’s Ford-engined sports cars and to race them. From 1952 to 1955, Zora drove in the 24 Hours of Le Mans, the first two years in Allards and the latter two in Porsches.  In 1952, Duntov returned to New York, where, a year later, he visited the Motorama at the Waldorf Astoria Hotel to see the new Corvette. That encounter inspired him to write a letter to Chevrolet’s Ed Cole, who in turn hired Duntov as an assistant staff engineer. Duntov, who eventually became the Corvette's chief engineer, made it his mission at GM to turn the

Corvette into a true sports car; to that end, he pushed for the small-block Chevrolet V-8 to replace the Corvette's six-cylinder engine.

Late in 1955, before the name “Corvette” became a household word signifying America’s sports car, a young Russian-born Chevrolet engineer named Duntov was toiling away almost anonymously in an effort to make his leftover factory mule into a record-breaker. Over a year earlier, Chevrolet Chief Engineer and three-time Indy 500 winner Mauri Rose had Daytona legend Smokey Yunick install an experimental V-8 engine into a 1954 Corvette test mule, which was given the factory designation EX87. When its testing duties were completed, it was given to Zora Arkus Duntov at Chevrolet Engineering to prepare for a high-speed record run at Daytona Beach.

Duntov’s mule was assigned a new tracking number, 5951. Duntov modified the car by replacing the windshield with a curved plexiglass windscreen adding a belly-pan and fitting a fiberglass tonneau cover over the passenger side of the cockpit to improve aerodynamics. Borrowing from recent Jaguar practice, Duntov also fabricated a fiberglass headrest-tailfin forhigh speed stability. In addition, they fabricated a tuned exhaust that Duntov designed himself. To Duntov’s dismay, the resulting speed was far short of his goal of 150 mph.

From his European racing days, Duntov knew that the camshaft was the one component that had the most potential to boost the engine’s output sufficiently to allow the Corvette to reach the target speed.  Duntov’s new  camshaft was quickly  fabricated and installed in the

 

ZORA DUNTOV'S MULE AT 2012 CONCOUR'S d'ELEGNACE