BMW releases a new set of photos featuring the 2013 BMW 640i. The inline 6-cylinder engine (N55HP) in the new BMW 640i Gran Coupe will impress performance-minded drivers with its effortless power, exceptionally fast-revving temperament, outstanding refinement and exceptional fuel efficiency. The N55 has been setting standards from the start, as the pioneer of a new generation of engines in which BMW TwinPower Turbo technology with High Precision Direct Injection and VALVETRONIC variable valve timing plus a twin scroll turbo made its debut.