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1956 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 led to nicknames 'Manx-Tail' and 'Bob-Tail.' The car had a wrap-around windscreen, a two-piece drop-down door, and an 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 Dan Vaughan

Sports Racer
Chassis number: CS/55/57

John Cooper is responsible for the rear engine revolution that has dominated the racing world since the sixties. Though the configuration was used by the 'Silver Arrows' team in their bulky grand prix racers, the practice had faded. Cooper moved the motorcycle engine that powered his tiny Formula 3 racer to the back to more easily accommodate its chain drive.

His success bred this 1100cc Coventry Climax powered and transaxle driven 'Bobtail' racer.

In mid-to-late 1954, Owen Maddock, at the Cooper Car Co., Ltd., began designing Cooper's new 1100cc sports car. At about that same time, Leonard Lee of Coventry Climax Ltd. allowed his engineers to begin production the FWA (Feather Weight Automotive) for the British specialists of that era. John Cooper was responsible for the decision to place the Coventry Climax engine in the rear of the new 1100cc sports car, but it was Owen Maddock who is credited with the unique and renowned design feature of the car now known as the 'Bobtail' or 'Manx-tail.'

This Cooper Bobtail is one of only 13 known survivors of the approximately 39 originally built. Although long identified as one of the 1957 cars, this Bobtail is actually a 1956 works car. The car appears to have been retained by the factory until the end of the racing season and then sold and thus creating confusion over the years of the manufacture. With its original chassis, racing scars helped identify this car as one of the cars that Jack Brabham raced along with other works driver Michael MacDowel. Mr. MacDowel drove the car at Goodwood on September 8th, 1956, at the Sussex Trophy Race.

This car was raced by Sir Jack Brabham along with other works drivers in period. This was Brabham's personal works car in 1956 as evidenced by correspondence with Michael MacDowel. Mr. MacDowel, also one of the works drivers, drove the car at Goodwood on September 8, 1956, at the Sussex Trophy race at the behest of Brabham and John Cooper. He finished 1st in class and 6th overall. With an impressive memory, MacDowel recalled that Brabham and John Cooper asked him to drive the factory Bobtail in order to allow Brabham to enter the race with his prototype Formula 2 car.

The Cooper Bobtail was an immediate success on the track. Many of the most successful drivers in racing history drove a Bobtail including Sir Stirling Moss. The Bobtail was a very successful endeavor for Cooper and was the first in line of the rear engine cars leading to the Formula 1 version that propelled Cooper back-to-back World Championships in 1959-1960. This little car changed the face of motor racing by moving the engine to the rear.

Sports Racer
Chassis number: CS11-12-56
Engine number: FWB 400/86877

Lacking proper purpose-built racing components, Cooper used what could be found. This led to experimentation and innovation, as is evident in the driver's center seating position within the tubular chassis. Another innovation was Maddock's short rear deck clothed in aluminum alloy, in similar fashion to the Kammback aerodynamic theory. From this, the T39 received its nickname of Manx tail or Bobtail.

The early T39 cars were powered by a Coventry-Climax FeatherWeightAutomotive 1100cc four-cylinder engine. The first competitive outing was in 1955 at Brands Hatch, where Ivor Bueb drove a T39 to 3rd place. Two examples raced at that year's LeMans ill-fated race, returning in 1957 where Jack Brabham and Ian Raby placed 15th overall and 3rd in class.

Charles Cooper asked Brabham to ship a T39 to Australia to compete in the 1956 Australian Tourist Trophy. Bill Patterson wanted to race a T39 as well, so one example destined for America was intercepted and re-routed to Australia. The Patterson car had been meant for the Briggs Cunningham team and wore the white and blue-striped livery. It was similarly equipped to the Brabham car, with power from a Coventry-Climax FWB 1460cc engine.

The Patterson car (originally intended to Cunningham) was this particular car, chassis number CS11-12-56. At the Australian Tourist Trophy, Brabham finished 11th overall and first in class. Patterson was forced to retire early from the race after rolling his car on the first lap. He returned on the meet's second weekend for a class win and 3rd overall. Patterson entered the T39 in the 1957 Australian Grand Prix but failed to start after gearbox problems occurred during qualifying.

The next outing for the T39 was at the 1957 Victorian Tourist Trophy where Patterson finished third overall and first in class. He placed second in the 1957 NSW South Pacific Championship at Mount Panorama. During the 1958 season, Patterson raced three times, with a class victory and second overall at the Victorian Hill Climb Championship.

Patterson then sold the car to Alan Jack, who raced it during 1959 and 1961. He finished 5th at the 1959 Australian Grand Prix, and 7th at the 1961 Australian GP. At the Australian Tourist Trophy, Jack finished 4th overall and 1st in class.

The car would pass through several more owners before being placed in a rural auto museum in Western Australia. This is where the present owner discovered the heavily campaigned old racecar. By this point in history, the original ERSA gearbox had been replaced by a Volkswagen unit. A restoration soon followed that included the replacement of many of the parts. To make it eligible for vintage racing, the car received a roll cage. The engine is a 1,460cc single overhead cam four-cylinder unit offering 108 horsepower. There is a four-speed manual transmission and drum brakes at all four corners.

After the restoration was completed, it was campaigned regularly at Australian vintage meets from 2009 to 2015, when the Cooper was damaged. The damaged body was replaced with a new body that was made to exact specifications, using another T39 for patterns.

by Dan Vaughan