In the mid-60s the Corvettes were rapidly catching the Cobras, Carroll Shelby and Ken Miles knew they had to add significant horsepower to the chassis if they were to keep winning everything in sight, and their partnership with Ford limited their engine choices to blue oval only.
The Shelby Cobra had originally been introduced with the Ford 260 cubic inch V8, an engine that balanced power and weight requirements well for the small car, and was able to fit into the engine bay. The original plans for an engine upgrade had been for an aluminium V8 that would either not significantly increase weight over the front wheels – or maybe even slightly decrease it. Sadly this was not to be, and Carroll was lumped with the solid but heavy Ford 427 cubic inch V8.
This new engine required the car to be re-engineered from the ground up, a new chassis was built from 3 inch steel tubing (the previous chassis was made from 2 inch tube) with an additional 5 inches of body width to allow the engine to fit into the new engine bay. The weight of the engine was an issue, and it required an entirely new independent coil spring suspension set up front and back – the 427 was installed as low and as far back as possible, but there was only so much space to work with considering the size of the roadster.
At the top of the performance ladder for the 427 variant was the Competition Cobra, just 23 were built in total and they’re now considered amongst the most collectible Shelby cars in existence. There were over 100 factory modifications for Competition 427 car including a roll bar, quick jack pads, magnesium Halibrand wheels, side pipes, and scoops for air and oil cooling.
The Competition Cobra you see here is the 10th one built, and it won the 1968 U.S. SCCA A Production Championship and the 1971 Eastern Canadian Endurance Championship – making it the only 427 Cobra to win championships in two countries. It was fitted with a refreshed engine in 2014 capable of 620 bhp, fed by a single Holley carburettor and sending power to the rear via an original 4-speed manual transmission.
It’s now estimated to be worth somewhere in the region of $2,500,000 to $3,300,000 USD, although it’s relatively easy to imagine that it’ll sell for more when it passes across the auction block with RM Sotheby’s on the 28th of January at the Arizona Auction. If you’d like to read more or register to bid you can click here to read the listing.
Photo Credits: David Bush ©2015 Courtesy of RM Sotheby’s
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