When John Cooper and childhood friend Eric Brandon returned form military duty, they decided that the time was right for them to build a car and begin competing. John's father, Charlie had been a mechanic to Kay Don, prior to the war, and owned a service station and Vauxhall agency, indeed John had been brought up around cars and racing, and they had the necessary contacts and tools to enable them to construct their own car. They decided from the outset that a small engined vehicle would be the most practical and after John visited Dick Caesar in Bristol, he immediately embarked on the build of a car to the new 500cc National Regulations which had just been laid down by the 500 Club.
Front suspension came directly from a crashed Fiat 500 "Topolino" which was lying in the garage yard. The Fiat was light and an advanced design for it's time, featuring independent suspension by lower wishbones and a single leaf spring across the chassis which provided upper location as well as supporting the car. Rear suspension took some pondering, due to the complexities of arranging drive to the wheels, but John hit upon the idea of using the same Fiat front suspension at the rear thus achieving a simple, all independent arrangement. The engine was a JAP speedway engine which were difficult to obtain at the time but Charles Cooper's motorbike connections ensured that Coopers got theirs. The disk wheels and steering gear also came from the Fiat.
The chassis consisted of a simple ladder frame with a series of hoops to support the body and provide additional structure to prevent the ladder from twisting. An attractive aluminium body was made for the whole car by a specialist, Charlie Robinson and is noticeably more comprehensive than most other specials of the time. Most of the body was permanently fixed to the frame, adding to rigidity with the cowls over the engine hinged to allow access. The fuel tank was placed behind the driver's head to form a cowl and gravity feed the Track carburettor below. Crucially, and for largely practical reasons, the engine was placed in the middle of the car, driving a chain to the Triumph Speed Twin gearbox and a second chain to the rear axle. The mid-engine layout had been used before, of course, but coupled with light weight, a low polar moment of inertia and all independent suspension, gave the car excellent handling characteristics. The faux radiator grill did in fact serve a purpose, ducting behind leading back past the driver to the engine for cooling and the slot in the tail provided an exit for the exhaust. The wheelbase was 80 inches, track 46 1/2 inches and she stood 35 inches tall in spite of a rather high ground clearance of 7 inches.
Two Prototype Cooper cars were built, the first (which they shared for a time) was for John Cooper and the second for Eric Brandon which was slightly longer as he felt cramped in the cockpit of John's car and incorporated a number of minor revisions including some drilling, a switch to Hardy-Spicer drive shafts and the "radiator" grill which would appear on subsequent production Coopers. The cars were retrospectively given the type numbers of T2 and T3 (T1 was given to John's Austin 7 Special).
Construction of the first car began in June 1946 and took about five weeks, in spite of Charlie's insistence that all work must be after hours and it made it's debut at Prescott Hill in July. Early performances were mixed, it was clear that the car was capable but inevitable problems of inexperience showed in the driving (John over revved the engine and bent a valve) and the engineering (The engine and gearbox mounts were simply not up to the job of dealing with the torque and vibration of a 500cc single cylinder engine). However, the car attracted considerable interest both for it's obvious speed and it's well executed design and construction. It wasn't long before other 500 hopefuls were enquiring as to the possibility of a production car.....
John and Eric continued to campaign their prototypes throughout 1947, John finishing 2nd and Eric, 3rd at the "White Hart" meeting in May, Eric winning at Prescott in June but the car really came to the fore when Eric won the first post war race at Gransden Lodge in July. John and Eric were present at the first attempt at competition by the 500 Club on the 25th October 1946 at Silverstone (see Keith Gough's From Acorns to Oak Trees), which eventually took place at Towcester, when this photo was taken by Edward Cannock.
The original prototype was sold at the end of 1947 to Stan Goddard of Southampton. It all but disappeared, although it briefly reappeared in 1953 in the hands of WR Croysdill. Whilst for 1948 John and Charles Cooper had the first two production chassis (the works 500 and 1,000), Eric would stick with T3, albeit with a new nosecone in the new corporate style. For 1949 Eric took over the works Mk III and the car was eventually sold to Ireland, turning up in the hands of Cromie McCandless, brother of Rex McCandless..
The following article, written by John himself, featured in Iota, April 1947 and outlines their early experiences with the Cooper 500. At the time of writing, Cooper garages had already taken the first steps to becoming a constructor with the Mk I (T4), a two seater sports car based on the 500 chassis and a production run of Mk II (T5), similar to the prototype car.