1955 Cooper T39

Charles and John Cooper had built a successful company based around their 500cc Formula 3 racers, when they introduced the Cooper T39 'Bobtail' 1100cc racer in the mid-1950s. The T-39 Cooper cars were creative and employed aerodynamic principles to minimize drag. The overall weight of the vehicles was extremely low, giving the Climax FeatherWeightAutomotive (FWA) engine as much support as possible, as the powerplant produced around 75 horsepower. Adding to its performance characteristics was its mid-engine layout and adding to its appeal was its relatively low price tag.

The cars had a tubular chassis with the driver positioned in the center of the car. The suspension was comprised of a transverse leaf springs setup with a tubular lower wishbone. The gearbox was a Citroen front-wheel-drive unit that was turned around and fitted with special 4-speed close-ratio gears and shafts. Drive was to the rear wheels.

The bodies were round and had a cut-off tail with a concave rear panel. This lead to nicknames 'Manx-Tail' and 'Bob-Tail.' The car had a wrap-around windscreen, a two-piece drop-down door, and a 8-gallon fuel tank mounted right behind the front wheel. For longer races, a larger fuel tank could be fitted, holding up to 14 gallons of fuel.

In 1955, the factory Bob-Tail T-39 made its racing debut at Goodwood in the hands of Ivor Bued, who drove it to a third place finish. Jim Russell drove a second T-39 factory car. In total, between 30 - 50 examples of the Bobtail were produced, including the 1956 and 1957 cars.

by Daniel Vaughan | Dec 2009