The 2015 BMW Z4 is a 2-door, 2-seat Convertible, available in 3 trims, ranging from the sDrive28i to the sDrive35is. Upon introduction, the $48,950 sDrive28i is equipped with a standard 2.0L, 4-cylinder, engine that achieves 22-mpg in the city and 34-mpg on the highway. A Manual transmission is standard. The $65,800 sDrive35is is equipped with a standard 3.0L, 6-cylinder, engine that achieves 17-mpg in the city and 24-mpg on the highway. An Automatic transmission is standard.