The souped-up hardtop version of the Z4, with the same 330 horsepower engine and suspension set-up of the Z4 M Roadster, is an unabashed track car. It makes no apologies for its hard ride, engine and tire noise, and lack of sound-proofing, but in return provides the Roundel enthusiast with a good basis for improving driving skills at BMW Car Club track events. -autosaloon.blogspot bring you to the limit.