BMW launched its Z4 roadster as a 2004 model. For 2006, the racy two-seater with sharp-edged styling (what BMW calls "flame surfacing") experiences its first major evolution with two new model designations and freshened styling inside and out. Both the Z4 3.0i and the Z4 3.0si are propelled by a more powerful engine. Manual and automatic transmissions get six gears. Also standard are 17-inch wheels, more powerful brakes, and Dynamic Stability Control technology.
BMW was the first automaker to launch a premium two-seat roadster, introducing the Z3 as a 1996 model that made its debut in the James Bond movie GoldenEye. The car was re-designed and re-launched in 2003 as the Z4. A high-performance M Roadster version also is available, with special engineering by BMW's M (Motorsports) Division. The M Roadster draws its power from a 3.3L inline six-cylinder engine that also resides in the M3, and in this iteration pumps out 330 hp. This special high-performance version of the Z4 also is equipped with other components (suspension, brakes, etc.) that balance its increased horsepower and dynamic capabilities.
The 2006 Z4 3.0si draws its propulsion from a 255-hp, 3.0L inline six-cylinder engine, while the Z4 3.0 gets 215 hp from its 3.0L I-6. While more powerful, both engines also are lighter than those used in the 2005 models. Either engine is available with a six-speed manual or six-speed automatic transmission. Automatics feature racing-style paddle shifters mounted on the steering wheel. The Z4's suspension was adjusted midway through the 2005 model year to enhance both ride and handling. For 2006, the updates continue with new 17-inch wheels and with standard Dynamic Stability Control technology that features new brake fade compensation, brake standby, automatic brake drying, and start assist, as well as an advanced anti-lock braking system. Brakes also have been enlarged, with 11.8-in. front discs on the 3.0i and 12.8-in. front discs on the 3.0si.
Design updates for the 2006 model year include new front bumpers with larger air intakes and rectangular foglamps, new wheel designs, new rear bumpers, and new tail light designs. Inside, there are more changes in the aluminum trim and climate control switchgear. Also offered are new colors for both cloth and leather seating surfaces. The Z4 is available with a 10-speaker, single-disc CD player or an upgraded Carver audio system. Also available are the standard manual convertible top or a power-operating roof. All Z4s have front and side air bags.
The BMW Z4 and M Roadster compete in the Compact Premium Sporty segment, a small but prestigious (and very competitive) category of cars with cutting-edge design and aggressive performance capabilities.
According to the J.D. Power and Associates Sales Report,SM the sales leader for calendar year 2005 was the Nissan 350Z with 27,278 units sold, followed by the Acura RSX (20,809 units in 2005), Mercedes-Benz CLK (18,227), Chrysler Crossfire (14,665), Mercedes-Benz SLK (11,278), BMW Z4 (10,045), Porsche Boxster (7,879) and Cayman, Honda S2000 (7,780), Saab 9-2X (5,940), Audi TT (2,822), and the Volvo C70 (1,442).