Honda CBR900 Cobra Prototype

– Quick Specs –

The odyssey of the Shelby Cobra is defined by the contributions of many people, marked by many important cars and by even more important moments. They weave a rich fabric of creativity, determination and persistence in the face of limited resources and epic challenges.

The saga of CSX 2196, the “Flip-Top” Cobra 427 prototype, is a bright thread in the tapestry of Shelby history.

The Cobra’s first race win came at Riverside in February 1963 in the hands of Dave MacDonald. Just behind him in second place after pitting on the first lap and dropping to last place was Ken Miles in another Cobra, a very precise, experienced driver who had made a name for himself on the West Coast. Miles soon joined Shelby as Competition Director, assuming a central role in Shelby’s frenetic pace of building and racing cars.

Miles was a Brit who spent the war wrenching tanks for the Royal Army and racing motorcycles when the chance, and a spare petrol ration, could be found. After the war he moved to Southern California as the MG distributor’s service manager and quickly hit the tracks, winning his first race at Pebble Beach in 1953 in an MG TD.

His TD-based Miles Special dominated California under-1500 cc events for years before it was succeeded by the [in]famous Flying Shingle, another TD-based special that was even lighter and more aerodynamic. Later, Miles drove Porsches for Johnny von Neumann but, unsatisfied with the cars from Stuttgart, built a Cooper-based, Porsche-powered Miles Special. He was so successful in it that Porsche eventually suggested to von Neumann that it was bad for the marque to be beaten by a distributor’s employee driving a Porsche-powered home-built.

Miles also was President of the California Sports Car Club which organized some of the most famous and important road races held in North America. What SCCA was east of the Rockies, Cal Club was on the West Coast. It was Miles who led it to success.

At Shelby, the lessons learned in the crucible of international racing at Nassau, Daytona and Sebring quickly were translated into improved designs and strengthened components. The Cobra finally realized its international potential in the 1963 FIA season’s last race, the 500 km test at eastern Long Island’s Bridgehampton Road Race Course where Dan Gurney and Ken Miles finished 1-2. It was the first FIA victory for a U.S. car with an American driver.

It was also the first victory for Ford power in an FIA sanctioned race.

The Cobra was a much hotter ride in late 1963 than it had been at the beginning of the season, but competition also was heating up with 4- and even 4.4-litre engines for Ferrari’s 250 GTO in the offing and GM readying the lightweight, disc braked Corvette Grand Sport for 1964. There was just so much that even Phil Remington and Ken Miles could do to the AC Ace-based 289 Cobra.

What Shelby had undertaken in late 1963 was amazing. They were building 289 Cobras. They were supporting SCCA and USRRC racers throughout North America.

They had a separate FIA Cobra for international events. There was a drag racing program. To compete on the major high speed circuits, the Daytona Coupes were being built, a complete evolution of the Cobra’s design accomplished in an almost unbelievable three months.

At the same time, mid-late 1963, Shelby took on the task of creating the Sunbeam Tiger prototypes, the racing car built in Shelby’s shop while in his own separate shop Ken Miles built the street prototype.

It was a breathtaking array of projects, but with one serious looming problem: the 289 Cobra was nearing the end of its competitive cycle. Competition – from Ferrari, Porsche, Aston Martin and potentially Chevrolet and Jaguar – was fierce. Ken Miles, involved in all aspects of Shelby’s myriad production, development and racing activities, was uniquely placed to see the future and took the project on himself.

Miles’ solution to the 289 Cobra’s situation? Fit an even bigger engine in the existing Cobra to see how the engine’s performance characteristics would relate to the chassis, then design, construct and develop chassis, suspension and bodywork in response to the new performance envelope.

It started with CSX 2196, the unique Cobra offered here. Ted Sutton stuffed a 427 big block into it, and the boss, Carroll Shelby, took it for a test drive (which must have been something to see). He came back with the concise instruction, “make it a race car.” Nearly every component in the car had to be strengthened to withstand the power and torque of the four-barrel NASCAR 427.

After testing in early 1964 at Riverside with the Daytona Coupe, CSX 2196’s first public appearance was at Florida’s rough Sebring airport circuit. During practice, it got away from Miles and smashed into a tree, an obstacle so rare at Sebring that the team modified his nickname “Teddy Teabagger” – based on his fondness for his afternoon “cuppa” – to “Teddy Treebagger.” Miles worked through the night to repair the damage done while he was at the wheel.

The 427 prototype took the green flag and Miles, who had hidden the fact he had broken ribs from the crash, drove the first two hours fighting teething problems and others arising from its hasty repairs. He was relieved by John Morton, who soldiered on through a series of stops to deal with clutch, fuel and brake problems until a blown engine eventually sidelined the 427 prototype, but not before it had shown its potential.

Upon its return to Venice, a comprehensive rebuild of CSX 2196 was undertaken to deal with its shortcomings. In addition to strengthening everything (again), the body was replaced by an imaginative aluminum structure in three pieces. The nose and tail were hinged at their extremities, flipping up and away from the center passenger’s compartment for instant access to suspension, engine, driveline and brakes. Doors were simple panels hinged at the bottom to swing out and down.

The hood and tail were lowered as much as possible to ease air penetration. It still looked like a Cobra, but one as described in the SAAC Registry “that had been lowered and slightly heated in the microwave.”

Its body made it ideal for its next job at Shelby, testing the new Ford engines for the next generation Cobra, called at that time the Cobra II. As described in a Ford memo from Ray Geddes, Ford’s liaison with Shelby, in August 1964 the first power was to be an experimental four-barrel aluminum block 390. After development and testing, it was to be replaced with an iron block four-barrel 427, then benchmarked against 289 and 325 cubic inch engines. The unusual body configuration earned it the nickname “Flip-Top.”

Sources dispute the origin of CSX 2196’s other nickname. Some, probably including John Morton who compared the original configuration’s handling at Sebring to a ’49 Buick, link it to the inevitable twitches associated with burdening a light chassis with a much heavier and more powerful engine. Others appreciated the potential of the power and torque from 138 more cubic inches operating at less critical rpm and suggested it was because it would “get up and @*%^ on the competition” or similar colorful language. In any event, it was quietly – mostly among the team mechanics – known as “The Turd.”

First tests of the aluminum 390 were conducted at Shelby’s familiar Riverside Raceway site. Subsequent testing and development is unclear. At the Flip-Top’s first public appearance at the Nassau Road Races in November and December 1964, some sources (including the SAAC Registry) describe it as alloy 390-powered.

Others give it 37 more cubic inches of cast iron Ford.

Honda CBR900 Cobra Prototype

Miles and the Flip-Top were accepted into the GT class along with the Corvette Grand Sports (GT Prototype) and Ferrari 250LMs. In the five-lap preliminary race on November 29, Miles finished ahead of all the Ferrari LMs and second to Roger Penske in one of the Grand Sports. Later in the day in the feature GT contest, the Nassau Tourist Trophy, the Flip-Top sat on the front row alongside Grand Sports driven by Roger Penske and Jack Saunders.

Ken Miles must have been sandbagging earlier, because on the opening lap of the TT, he smoked the Grand Sports, opening up a massive eight-second lead – enough to leave the Grand Sports a full straightaway behind.

Eventually differential problems slowed the Flip-Top, allowing Penske to catch up and enliven the race with a series of lead exchanges until the Flip-Top’s engine expired.

Back in Los Angeles, attention turned to devising the production 427 Cobra. The Flip-Top, eligible only for modified classes in competition with mid-engined sports racers, languished and was eventually offered for sale in late 1965.

Eventually acquired by Al Rivera of SC Motors in San Francisco, it was driven by Dave Ridenour in C/Modified races. Later it was sold to Mark King, then Dick Workman who installed a 302 Ford and later to Royal Krieger. Subsequent owners included Chris Gruys who brought it back to original specs with 427 Side Oiler power and began to vintage race it in 1980.

After a period in the famed collection of Bob Lee, it was acquired by its present owner in 1999 and since then has been regularly seen in West Coast vintage race events. In 2007 the Flip-Top Cobra 427 participated in the Goodwood Festival of Speed, its first international appearance since Nassau in 1964.

Powered by a Rex Hutchison alloy 427 Ford dynoed at 623 brake horsepower at 6,300 rpm and 611 lb-ft torque at 4,200 rpm, the Flip-Top 427 Cobra features extensively in all the definitive histories of Shelby American and the Cobra. It is the only prototype of the 427 Cobra and arguably the only “Cobra II” since that designation was not used for the production coil spring 427 Cobras.

Design of the production coil spring 427 Cobras was done by Ford engineers, making CSX 2196 effectively the only 427 Cobra designed and built by Shelby. It is the Cobra that blew off the Grand Sports at Nassau and the Cobra conceived, assembled, developed and raced by Ken Miles, one of the legends of American road racing.

Available now for the first time in over a decade, CSX 2196 is one of the legends of Shelby and Cobra history. Fully developed, absolutely unique and blindingly fast, it is a milestone in the legendary history of Shelby, the Cobra and the Ford Motor Company’s “Total Performance.” No tapestry of Shelby, Cobra or Ford racing history is complete without the thread of CSX 2196, the prototype 427 Cobra.

This car was auctioned off by RM Auctions in January of 2010 at the Arizona Biltmore Resort Spa, Phoenix, Arizona.

623 hp, 427 cu. in. aluminum block pushrod overhead valve V8 engine, four-speed manual transmission, four-wheel independent suspension with transverse leaf springs, telescopic shocks and anti-roll bars, four-wheel disc brakes. Wheelbase 90

Source: RM Auctions

Photo Credit: Copyright Donald Child

Honda CBR900 Cobra Prototype
Honda CBR900 Cobra Prototype


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