Porsche is completing the fastest ever generation change in the 911 model series. Two new power units with Direct Fuel Injection (DFI) improve both the performance and economy of the car, the fast-shifting Porsche Doppelkupplungsgetriebe (PDK) – or double-clutch gearbox – replaces the optional Tiptronic S automatic transmission, and electronically-controlled Porsche Traction Management (PTM) takes the place of the former viscous-coupling...