Ford Sierra RS Cosworth: the rep's car that became a legend (1986-1992) The Ford Sierra RS Cosworth turned an ordinary family Ford into a Group A touring-car weapon, with a turbocharged Cosworth engine, a whale-tail wing and, in RS500 form, near-unbeatable race performance. A guide to the three-door, the RS500, the Sapphire and the 4x4, what to look for, and why values have soared.
