Based on the updated 2006 BMW Z4 convertible, the M Roadster is a two-passenger performance car for enthusiasts who not only like driving with the top down, but enjoy doing so quickly while in complete control. To that end, the 2006 M Roadster comes equipped with a 330-horsepower engine, a speed-sensitive locking differential, high-performance brakes, and advanced technology like Brake Drying, Brake Standby, and Brake Fade Compensation.