and the 2.0 L BDA engine powered the majority of Ford's 1970s rallying successes.

With Ford's withdrawal from F2 in the mid-1970s, Hart began to concentrate on building their own designs. The first engine to bear the Hart name alone was the twin-cam, four-cylinder Hart 420R F2 unit, which appeared in 1976 and powered race-winning cars until the end of the decade. In 1978, the Toleman