The new Z4 comes as a folding hard top only, which allows comfortable motoring, top up or down. Competing with the Porsche Cayman, Boxster and Audi TTS, the Z4 sDrive35i utilizes a twin-turbo engine that makes 300 hp and 300 lb-feet of torque across a wide rev range. That's more power than the TTS, and with its hatchback cargo setup, more practicality than the Boxster.