Cosworth engines have powered their way to more than 100 Grand Prix victories. Tonight William Woollard revs up in the Sierra Cosworth, the first road car to carry the famous name, and looks behind the scenes at the company's Northampton headquarters. There are road tests on two of the winter's newcomers, the Peugeot 309 and Vauxhall's Belmont. Are the days of motorists struggling with road maps numbered? Chris Goffey travels to Holland to try out an amazing in-car navigation system.