A carry-over for 2006, the Z4 is a two-door, two-seat convertible or coupe sports car that’s offered as the 3.0, which features a 215 horsepower I6. The 3.0Si has an increased output of 255HP. A six-speed manual transmission is standard with a six-speed automatic as optional. The M trim is powered by a 330 hp 3.2L inline six-cylinder engine.