0 hour(s) and 00 minutes - Movie - 2010 The Ford Sierra RS Cosworth was a high-performance version of the Ford Sierra. It was the result of a Ford Motorsport project with the purpose of producing an outright winner for Group A racing in Europe. The second generation 4 door Sierra Sapphire Cosworth was assembled in Genk, Belgium, with the UK-built Ford-Cosworth YBB engine.