Shelby Cobra 427

In many respects, the father of the 427 Cobra was famed racing driver Ken Miles, who had driven many one-off specials with large-displacement V8 engines. While the 289 reached its reliability limit at around 390 horsepower, more output was required, as confirmed by the emergence of the new Corvette Grand Sport at Nassau’s Speed Week in 1963.

Although Shelby had been promised a new aluminum-block version of Ford’s FE-Series 390-cu. in. engine, internal resistance developed from the NASCAR faction inside Ford Motor Company. The alternative was Ford’s cast-iron 427 V8. Despite being reliable at 500-plus horsepower, it was so much heavier than the 289 that a complete redesign of the Cobra chassis was required to ensure proper handling. With the help of Ford’s engineering department, the necessary development work was done, and the 427 Cobra was introduced in 1965.

In order to qualify or homologate as a production car under FIA rules for the GT class, manufacturers were required to produce a minimum of 100 examples. Anticipating FIA approval, Shelby ordered 100 competition-spec 427 Cobra bodies from AC. When FIA inspectors arrived at Shelby’s facilities on April 29th, 1965, they found just 51 completed competition cars and refused to homologate the cars.

Once Shelby knew that the FIA was not going to allow the new 427 Cobra to compete in the GT class, he cancelled his order for the remaining competition cars, and AC reverted to road-going or street Cobra production. Then, in June 1965, the FIA juggled its classification system and created the new “Competition GT” class. This time, the production requirement was lowered to 50 – coincidentally, one less than the number of 427 competition cars built at the time of the FIA inspection.

The rule change created another problem for Shelby – it put his Cobra in the same class as Ford’s GT40. Since Shelby was running that program for Ford, there was a clear conflict of interest. To resolve it, Shelby agreed not to campaign his own car, leaving the racing Cobras in the hands of privateer teams.

Regardless of the model – full competition, “S/C” semi-competition or regular street specification – Shelby’s 427 Cobra was a sports car unlike any other. Performance was mind-blowing, with the Cobra’s extraordinary power-to-weight ratio allowing for an incredible 0-100-0 mph sprint in an astounding 13.2 seconds, as reported in Sports Car Graphic magazine.

Part of the RM Auctions event in Arizona in January, 2010; in California in August, 2010 and in Arizona in January, 2013.

450+ hp, 427 cu. in. Ford side-oiler V8 engine, single four-barrel carburetor, four-speed manual transmission, four-wheel independent coil-spring suspension, rack-and-pinion steering, and four-wheel hydraulic disc brakes. Wheelbase: 90"

Source: RM Auctions
Photo Credit: Copyright Simon Clay and Darin Schnabel

Shelby Cobra 427