Production: 1971 - 1997
Jaguar had experimented with a V12 design during the early 1950s, Heynes and Baily constantly discussing and making notes about how it should proceed so drawings of a V12 engine were in existence in the late 1950s.
When Jaguar purchased Coventry-Climax in 1963, Hassan returned to the experimental department and, together with Baily, was tasked to further develop the V12 engine that already existed on paper. Harry Mundy, who had designed the Flat 16 engine for Coventry-Climax, also joined the small team. The plan for a race engine – particularly for Le Mans – and a second version for road-going Jaguar sports and saloon cars was revived and work proceeded with a V12.