Property of a deceased's estate c.1950 Cooper Formula 3 Single-Seater Chassis no. 54750 Engine no. 75819
Powered by JAP and Manx Norton motorcycle engines, Cooper's innovative rear-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. Charles and John Cooper's first post-war racing car (there had been a one-off trials special built in the late 1930s) utilised the chassis of a crashed FIAT Topolino. FIAT transverse-leaf independent front suspension was used at both ends and the single-cylinder 500cc JAP motorcycle engine was positioned behind the driver, this being the easiest way to accommodate the motorcycle transmission's chain final drive. The Coopers' friend Eric Brandon drove a MkI to victory in the first-ever 500cc race in 1947 and before long the Cooper had established itself as the car to beat. The resulting flood of orders meant that relying on a supply of crashed Topolinos was out of the question, and the Coopers set about designing a car that could be built from scratch, powered in its initial form by the ubiquitous 'Speedway' JAP engine. Over the course of next decade the F3 Cooper gained rack-and-pinion steering, pannier fuel tanks and a proper tubular-steel spaceframe chassis among numerous other improvements as development proceeded through Marks I to XIII, while the JAP engine gave way to the overhead-camshaft Norton Manx unit. This JAP-engined Cooper Formula 3 monoposto is believed to have been fitted originally with a 1,000cc twin-cylinder engine, those of JAP and Vincent being most commonly used in period. It is also believed to have been owned by the late Ken Wharton. We are advised that the car has seen little competition use and that it lay in store in Surbiton for several years. '54750' now has a single-cylinder JAP engine installed, which is fitted with a steel connecting rod and set up to run on methanol fuel. The car is described as in generally good/very good condition and offered with a trailer, a spare engine, four tyres and previous owner correspondence.