After the elegant but delicate Lotus Elite of the 1950s, which featured a complete fibreglass monocoque fitted with built-in steel pickup points for mounting major components, Lotus found critical and sales success in the 1960s with the Lotus Elan two seater later developed to two plus two form. Lotus was notable for its use of fibreglass bodies, backbone chassis, and overhead camshaft engines, initially supplied by Coventry Climax but later replaced by Lotus-Ford units (Ford block, Lotus head and twin cam valve gear). Lotus worked with Ford on the Lotus Cortina, a successful sports saloon.