For the Shelby Cobra, thank Chevy’s Corvette - and diseased chickens

“When I first saw the Shelby Cobra,” said Dan Gurney in recollection of a day at Riverside Raceway, California, in spring 1963, “it looked almost laughable. Here was a British sports car with pre-World War II design features that had received a California hot-rod makeover.” And when Gurney got behind the wheel of the Cobra, it seemed to him even more unorthodox. On Sicilian mountain roads in the Targa Florio, he said, it “was like riding a bull . . . a belching, bucking, vibrating brute of a machine.”

But here’s the rub: “Once you tamed the beast,” Gurney said, “the Cobra delivered the most outstanding lap times. Its creator Carroll Shelby, visionary and superior salesman, sold Ford Motor Company on the idea that the Cobra could beat the Corvette. And it did!”

This explains why The First Three Shelby Cobras, the latest title in our Exceptional Cars Series, promises the story of “the sports cars that changed the game.” It’s a story that was made possible by two quirks of fate. One, as Gurney mentioned, was the eye-catching existence of the Chevrolet Corvette. The other, less frequently mentioned, was an outpouring of watery greenish diarrhoea.

The Corvette? This blessed the Chevrolet brand with a halo effect which Ford envied but was unable to mimic because it lacked a suitable sports car of its own - so when Shelby needed an engine for a high-performance roadster and went pushing on Ford’s door, it was already half-open. And the effluence? This is one of the gruesome symptoms of Newcastle disease, which wiped-out 80,000 chickens owned by Shelby when he was a farmer - so provoking him to change career direction.

Shelby hadn’t long been in his new career, racing an Allard J2X, when his eyes were opened to the benefits of combining a British chassis with an American V8. Soon he had dreamed-up a more modern mid-Atlantic recipe of his own with ingredients every bit as tasty as the home-baked Corvette’s: a 260cu.in. (4.2-litre) V8 from FoMoCo in Dearborn, Michigan, plus a chassis and body from specialist sports car maker AC Cars in Thames Ditton, Surrey. The resulting concoction, to start with at least, was a car similar in appearance to the AC Ace which sired it, which meant few people outside Ford or Shelby recognised that it should be taken seriously. But the Cobra’s effectiveness on-track, plus a series of technical developments forged in the hothouse of competition, soon changed all that. On the snaking circuits visited by the Sports Car Club of America and the United States Road Racing Championship, the Cobra was a competition-killer.

Shelby’s dreams, however, were bigger than this. He wanted his car to go racing in Europe. Moreover, he wanted his car to “whip Ferrari’s ass.” This would mean entering the Le Mans 24 Hours, which Shelby had won when driving for Aston Martin in 1959 and Ferrari had dominated every year since. A bold ambition, but one in which Shelby and Ford again found themselves aligned: Henry Ford II’s last-minute rejection when attempting to buy-out Ferrari in May 1963 had given him, too, the compulsion to kick Enzo where it hurt.

Shelby knew, of course, that the Cobra wasn’t quite up to the job. It had too much of an aerodynamic disadvantage, because of its open top, to match the straightline speed of the swoopy-roofed Ferrari 250 GTO. So the Cobra roadster evolved into a car with a lid - and when the Daytona Cobra Coupe won its class in the 1965 World Sports Car Championship, Shelby and Ford had a sweet taste of the victory over Ferrari they craved.

Both Cobra and Daytona strengthened Shelby’s involvement in the Ford GT40 programme, leading to the Shelby-American team’s back-to-back victories - yes, defeating Ferrari! - with the GT40 at Le Mans in ’66 and ’67. In the second of these Le Mans triumphs, one of Shelby’s two winning drivers was AJ Foyt, who had just scored his third Indy 500 victory. And the other driver, a talented racer-cum-engineer who would also win the Belgian Grand Prix at Spa a week later in an Eagle-Weslake of his own construction, was Daniel Sexton Gurney.

By Phillip Bingham