In 1959, the mid-engined Cooper T51 that won the Formula 1 championship signalled a revolution in design, a design seized upon by Colin Chapman. The transition from front-engined to mid-engined was an obvious one for Lotus, now that the concept had proven to be a winner.
Lotus produced mid-engined Formula 1 cars from 1960 onwards, but Chapman had his sights set on another prestigious race: the Indianapolis 500. The first mid-engined Indycar, the Lotus 29, appeared in 1963 to the great consternation of Indy traditionalists, whose cars were front-engined and mostly powered by four-cylinder Offenhauser engines. Formula 1 's engine size at the time was only 1.5 litres, so Chapman made a deal with Ford to use its fuel-injected, 4.2-litre, small-block V8. Entered in the 1963 Indy 500 and driven by Jim Clark, the car finished in second place behind a front-engined Watson-Offenhauser.
In 1964, with a new Lotus 34 and more power (500bhp) from a new fuel-injected, four-overhead- camshaft version of the Ford V8, Clark returned to the Brickyard and set record speeds. However, in the race a Dunlop tyre began to delaminate, which resulted in a heavy crash into the wall, fortunately without injuring Clark.
For 1965, Chapman and Lotus engineer Len Terry came up with the Lotus 38. Using an aluminium monocoque rather than a spaceframe, its suspension was offset to move the chassis to the left so that it sat closer to the inside of the track, the better to handle cornering forces on the banking of the anti-clockwise Indy circuit.
The Americans had now overcome their scepticism about the mid-engined concept, and all but four cars on the 1965 Indy 500’s grid were thus configured. Clark broke the 160mph qualifying barrier and led for the majority of the 200-lap race, most importantly on the last lap. Three of the four cars on the same final lap were Lotus-built.
Clark’s win was a seismic moment in motorsport history, for no other front-engined car won Indy again. But this first all-British Indy win also confirmed that the UK motorsport industry was a leading force, and that Clark was a global star.