PORSCHE's new 911 Turbo Cabriolet will be launched here on Sept 14, a day after it is unveiled at the Frankfurt Motor Show. The 3.6-litre bi-turbo six-cylinder 'boxer'' engine generates 480 horsepower and 620Nm of torque at 1,950rpm. With an overboost function, torque goes up to 680Nm briefly. The manual version hits 100kmh in four seconds, while the Tiptronic S does it in 3.8 seconds. Both will max out at 310kmh. Prices start from $684,888 with COE.