The Lightweight E-Type made extensive use of aluminium alloy metal, in the body panels and other components. However, with at least one exception, it remained an open-top car in the spirit of the D-Type to which this car is a more direct successor than the production E-Type which is more of a GT than a sports car. The cars used an aluminium block tuned version of the production 3.8-litre Jaguar engine with 300 bhp (220 kW) output rather than the 265 bhp (198 kW) produced by the ordinary version.
Factory-built lightweights were homologated by Jaguar with three 45DCO3 Weber carburettors in addition to a Lucas mechanical fuel injection system. Early cars were fitted with a close-ratio version of the four speed E-type gearbox, with some later cars being fitted with a ZF five speed gearbox.
The cars were entered in various races but, unlike the C-Type and D-Type racing cars, they did not win at Le Mans or Sebring but were reasonably successful in private hands and in smaller races.