1956 Cooper T39 Bobtail
Estimate: £110,000 - £140,000
1956 Cooper T39 Bobtail
Chassis no. CS/3/56 (see text)
*Landmark Cooper sports-racer
*Sold new to Alan Mackay
*In-period race history
*Known ownership history
*1,460cc Coventry-Climax engine
*Fresh FIA Historic Technical Passport
Powered by JAP and Manx Norton motorcycle engines, Cooper's innovative mid-engined racing cars dominated the 500cc Formula 3 scene in the 1950s, providing many future stars, most notably Stirling Moss, with their first taste of 'real' motor racing. What had been a strictly pragmatic solution to the problem of accommodating the motorcycle transmission's chain final drive resulted in a superbly well balanced car, and this demonstrably superior arrangement was continued on the next generation of Cooper sports-racing and single-seater designs. When the former first appeared in 1955 it featured a centreline driving position and an abruptly truncated tail, immediately gaining the sobriquet 'Bobtail' or 'Manx'.
Crucial to the development of this new family of Cooper competition cars was the availability of the Coventry Climax FWA (FeatherWeight Automotive) engine, a four-cylinder, single-overhead-camshaft, all-aluminium unit developed initially to power fire pumps. Designated 'T39', the new sports-racer boasted a tubular steel chassis laid out on traditional Cooper lines, with transverse leaf springs and wishbones at both ends, while the mandatory 'passenger' seat was placed to the left of the driver. A Citroën 'Traction Avant' gearbox, reversed and fitted with an ERSA close-ratio four-speed gear cluster provided the transmission. The little Cooper's most talked-about feature, though, was the chopped-off tail, which had been inspired by the theories of German aerodynamicist, Dr Wunibald Kamm. Top speed with the 1,098cc FWA installed was around 125mph.
Ivor Bueb, who would win the Le Mans 24 Hours with Mike Hawthorn in a Jaguar D-type two months later, debuted the works prototype T39 at Goodwood on Easter Monday 1955, finishing 3rd after battling with two 1.5-litre Connaughts. Further good results, including Bueb beating all the 2-litre cars at the May Silverstone meeting and winning the 1,500 class, led to orders flooding in.
Although factory records are incomplete, this example can be traced through continuous ownership and a reference in Doug Nye's celebrated 'Cooper Cars' book back to its purchase by Australian Alan Mackay. This car has always been known as 'CS/3/56', and is replica plated as such, although it may not have carried a plate originally. Having competed in a few acclimatisation events in the UK, including the famous Prescott hill climb where he finished 3rd, Mackay had the factory run 'CS/3/56' alongside its own cars in the 1956 Shell Cup race at Imola, Italy before shipping it home to Melbourne. Indeed, after Mackay's car had split its gearbox casing during practice, Cooper works driver and general dogsbody Jack Brabham (the future three-time Formula 1 World Champion) selflessly worked all night to repair it for his compatriot, sacrificing his own car's preparation to do so.
According to John Blanden's 'Historic Racing Cars in Australia', Mackay's T39 made its Australian debut at Albert Park in March 1957. It was then shipped to New Zealand, reportedly clocking 137mph on a runway at the Wigram airfield circuit outside Christchurch - an impressive figure for an 1,100cc car. Sold on its return to Australia to Lyn Archer of Tasmania, the car finished 6th in the 1959 Australian Grand Prix, a Formula Libre race held on the island state's Longford road circuit. Subsequently damaged by fire after a fuel line split, the car was sold during its rebuild to Ray Gibbs of Melbourne, who had the engine enlarged to 1,216cc. The next owner, Jim Downey of Sydney, then fitted a Porsche engine for Bathurst in 1962, but the Cooper was now six years old and un-competitive.
In the 1970s, David Medley commissioned race-car builder Dave Mawer to start a full restoration to original specification. George Goodare completed the work, then sold the car to American Art Valdez, who ran it at the Australian GP supporting event at Adelaide in October 1986 and Sandown Park, Melbourne, in '87 before shipping it back to the USA. The current vendor purchased 'CS/3/56' in the USA some 18 months ago.
This Bobtail is described by the vendor as in excellent condition throughout, finished in British Racing Green with 'Coventry-Climax' lettering on its nose. The 1,460cc engine's sump has been removed by Hawker Racing for inspection of the crankshaft and bearings, which have been given a clean bill of health. A leak-down test revealed good compression and the engine runs crisply. With wheel cylinders replaced, clutch slave cylinder inspected, and new master cylinders fitted, the car is ready to resume its competition career.
Cooper T39s are proven giant-killers, engaging to drive and are regular invitees to prestigious events such as the Goodwood Revival. They are also welcomed in the Motor Racing Legends' Woodcote and Stirling Moss Trophy series, GT & Sports Car Cup, FiSCar, and VSCC events.
With a renewed FIA HTP, 'CS/3/56' presents an opportunity to compete amongst some of the greatest GT & Sports racing cars of the 50s and 60s at iconic circuits such as Silverstone, Spa, Goodwood, and Donington.
Please refer to Bonhams Motor Car Department for further information.