Shelby American Cobra 260

The Shelby American Cobra 260 traces its roots back to the British AC Ace and later AC Bristol engined version. A tubular and lightweight design enclosed in a beautiful aluminium body originally designed by John Tojeiro.

Carroll Shelby, of previous Le Mans fame with an outright overall win in 1959, convinced the British manufacturer to supply chassis that would be brought onto US soil for the fitting of a Ford 260ci (4279cc) Fairlane engine as a first development but above all with the Ford Motor Company onboard. Chassis were tweaked to ensure that the bigger and more powerful engine would not disrupt the handling of the car or its reliability, as they were somewhat different to the Ford stock units with specific camshafts, porting and altogether breathing through a Holley 4 barrel carburettor.

As development became finalised, the manufacturing of the production version started in 1962, the ultimate aim being to achieve the FIA homologation standard of 100 cars built for Grand Touring registration. This would be achieved on the 11^th of September 1962, with the FIA granting homologation 79 to the car on the 8^th of October that same year.

Shelby American Cobra 289

The Cobra 289 evolution came together for 1963 through the work of Carroll Shelby and his association with the Ford Motor Company. The Cobra 260 had proved the concept, but Shelby knew that if he was to take over the World Championship for Makes, he would need to up his game. This came through the development by Ford of the 289 V8 engine, a 4700cc engine that would produce around 330-340 horsepower, and which would be compact enough to be handled by the British-built but American-developed race bed.

The Cobra 289 was a true evolution of the previous model and was not just about an engine swap. The geometry of the front suspension was revised, the worm and roller steering system followed on from the late 260 models with the fitting of a steering rack. Alongside those changes, the body saw the appearance of small side vents on the wings, adding a little sporty touch to the lightweight Anglo-American roadster listed with a kerb weight of 985kg.

In competition, the car proved to be a killer with the American establishment in the 1963 season, as Shelby American took the overall American SCCA title, while the model and production reached the minimum required with the FIA and homologation 115 was granted by the 10^th of May 1963. Europe was now in sight, as was the World Championship for Makes; the Ford Total Performance effort was on course, with Shelby American overseeing the Grand Touring duties.

In racing trim, the car crossed the Atlantic to Le Mans, France, as early as June 1963 with two works supported cars: one through Ed Hugus for the “American” entry identified as “645 CGT”, and the other one through AC Cars Ltd. and named “39 PH” as the British entry. The American car did not finish due to an engine failure, while the British car finished 7^th overall and behind the regular European entries of Ferrari and the mighty 250 GTO.

Lessons were learnt and along with the development that was going on in the US, Shelby, in association with Peter Brock, started the design of the Daytona Coupe to tackle the issue of aerodynamics that the Le Mans hardtop was unable to overcome in order to up his game to Europe’s standards.

1964 was to see a full Shelby works effort in the World Championship for Makes from the start of the season in Daytona and Sebring, as well as the first entries for the newly developed Daytona Coupe alongside the so-called FIA Roadster regular cars. The Shelby American show would go on to shake the establishment in Europe as well, with notable wins at the Targa Florio, 24 Hours of Le Mans and the RAC Tourist Trophy in the Grand Touring category, but was ultimately to finish second to Ferrari. That was subsequently reversed in 1965, with Shelby American and the Cobra taking full honours and the title that year – finally, Ferrari and Europe had been beaten.

Shelby American Cobra 289 “Daytona Coupe”

The Daytona Coupe is the special bodied version of the Cobra 289 and traces its roots to an Appendix J freedom that stipulated that, once past the 100 cars manufactured for homologation, manufacturers could use a special bodied version of their cars provided that the mechanical components remained as homologated. This is the concept that also permitted the Ferrari 250 GTO or Jaguar “Low Drag” E Type to take shape.

While it is now safe to say that a few tubes were added if compared to a standard Cobra 289, all in all Peter Brock managed to produce an aerodynamic concept which proved efficient for those dark ages of automotive aerodynamics. Brock, of GM origin before joining the Shelby operation in Venice, California, used a concept paper dating all the way back to the 1930s and written by Dr Wunibald Kamm in Germany which he witnessed back there. Nobody had foreseen that the figures and details would produce such an efficient package, masculine if compared to the voluptuous Ferrari 250 GTO but nevertheless an effective one. It took 90 days to build the first car and get it racing at Daytona in 1964 where it showed its speed, even though the car retired following a pit fire incident.

As a special bodied version, it required a few changes that translated into a specific exhaust manifold, but other than that, most changes were about aerodynamic efficiency or, if looking at the engine bay, about hot air flow and airbox arrangements. The car also sports a different dashboard consisting of an alloy sheet with Stewart & Warner gauges with rear view to an aerodynamic spoiler on the back end.

The first car was built in Venice by Brock and the Shelby team themselves, while the other 5 cars were subsequently manufactured by Carrozzeria Gransport in Modena, Italy.

The Cobra Dos and Don’ts in FIA historic motor sport:

• Shelby American Cobra 260
• Pre-63 specification allows for the use of a small windscreen as homologated and visible on the homologation and/or a standard windscreen as manufacturer equipment. Hardtop falls under the same freedom from period.
• Pre-63 specification does not allow for upward carburettor intake manifolds, nor does the 4 into 1 exhaust manifold seen in the homologation form and its Page 9 which is dated 1963. Only the elements described in the form on Pages 4 and 8 can be used. The cars cannot use Uniball joints suspension pick-ups under any circumstances.

• Shelby American Cobra 289
• The cars can use Uniball joints suspension pick-ups.
• The use of the production specification wire wheels is permitted (F and R 15×7^1/2).
• Factory standard Girling 16/3 brake callipers are permitted as an alternative to the competition standard specification Girling CR and ORA (with handbrake) callipers.
• Gearbox details and acceptance can be found as an additional document in manufacturer’s documentation – see here. Hurst quick shifters were neither homologated nor used in FIA-sanctioned events in period.
• There are exhaust manifolds specific to the roadster and Daytona Coupe:
• 4 into 1 each side between the chassis and engine block for the roadster.
• Double 2 into 1 each side for the Daytona Coupe.
• Freedom is given for the line to allow for silencers down each side.

• Body
• The Cobra 260 can only sport the short hard top.
• The Cobra 289 can sport either the short or the Le Mans hard top.
• When it comes to wheel arches, Dunlop arches or so-called “FIA Roadster” cars, the fitting of a hard top will be considered in accordance with best practices given to other cars and a combination of the various period versions, this is because these cars today mostly use a 6-point ROPS. Daytona Coupe cars must pay specific attention to the shape of the bonnet hump above the carburetors. Period pictures show that the hump did not follow the shape of the bonnet in its forward part and then leveled with the leading edge of the windscreen.
• The Daytona Coupe sported a single air intake at the front of the bonnet, divided to feed the various internal components including the brakes. The lights fitted to each side cannot be replaced with air intakes to serve the purpose of brake cooling.