Tyre Size: 145/80R15 (145R15) | Lotus Seven S1 1957 to 1960
The original version of a minimalist sportscar for the road. Built from 1957 to 1960. Originally fitted with a now unavailable 520-15 crossply tyre. A modern radial replacement would be a 145SR15.
Still in production in Caterham form more than 60 years after its launch, the Lotus Seven revolutionised the affordable sports car market when it made its debut in 1957. Taking over where the Lotus Six left off, the Seven featured an even lighter tubular chassis, coil spring and wishbone independent front suspension plus rack-and-pinion steering taken from the Morris Minor.
Fitted with an Austin Metropolitan rear axle and 15-inch steel disc wheels (wire wheels were a rarely fitted optional extra), motive power was courtesy of a Ford 1172cc 100E side-valve engine, while stopping power was via drum brakes front and rear.
Even with the 40bhp Ford engine the Lotus Seven could top 80mph, but from 1958 a 75bhp 1098cc Coventry-Climax engine was offered which turned the Seven into a real flier. Whereas the 100E-engined Seven was known as the 7F, the Coventry-Climax car was the 7C; in 1959 the 7A was introduced with a 948cc BMC A-Series engine with just 37bhp.