The central arm rear axle also uses twin-sleeve gas-pressure shock absorbers and an anti-roll bar to provide the best link between the rear axle subframe and body of the car to achieve the smoothest ride from the stiffest possible chassis.

The M Coupe takes things a step further. Engineers from BMW M have transferred brake and suspension technologies from the renowned M3 CSL to give the new Z4 M Coupe superb handling and braking characteristics. Drilled and vented 345 x 28mm front brake discs and 328 x 20mm discs on the rear are mated to the CSL's floating callipers. This ensures that the Z4 Coupe stops from 62mph in just 34 metres. The drilled discs not only aid cooling and braking but also reduce the unsprung masses of the car by three kilogrammes, thus further enhancing the car's handling capabilities.
 
In the same vein, M3 CSL suspension components are adopted. For example, the single-joint front axle with McPherson spring struts, forged aluminium track control arms and separate mountings for the springs and dampers. All were developed on the punishing northern loop of the Nurburgring and offer the Z4 Coupe a firm, yet compliant, ride.

The front track of the Z4 3.0si Coupe measures 1,473mm with the rear 1,523mm. Combined with the near perfect 50:50 weight distribution and a low centre of gravity, this offers exemplary handling characteristics, especially when cornering. Customers opting for the Sport model Z4 3.0si Coupe receive a more sports-orientated suspension set-up. The Sports Suspension is stiffened and lowered by 15mm compared to a Z4 3.0si SE Coupe. 

The M variant, with the benefit of its Variable M differential, enhanced suspension set-up, lower profile tyres, different track widths (1,486mm at the front and 1,516mm at the rear), and 10mm lower chassis height takes those handling characteristics to an entirely new level.



Electric power steering - reducing fuel consumption

The BMW Z4 3.0si Coupe features the same electrically-assisted Servotronic steering from the Roadster. With its electrical assistance, engine power normally needed to drive a hydraulic steering pump is reduced, equating to a reduction in fuel consumption of one litre per 250 miles. 

Designed to balance the requirements of around-town driving with those of the open road, the electrically-assisted steering of the Z4 Coupe offers a fixed ratio of 14.2:1 to provide 2.4 turns lock-to-lock and a turning circle of 9.8 metres. The rack and pinion system is aided by BMW's Servotronic speed-proportional steering assistance for ease of manoeuvrability.

Engineers from BMW M, however, evaluated the characteristics and benefits of the electrical-assistance system against the core values of an 'M' car during development. Following thousands of miles of evaluation on the Nurburgring, BMW M decided to equip their car with conventional hydraulic assistance. In their view, this offered the correct level of steering feel for a 'motor sport' derived production car.



Safety and technology

With its high performance engines and agile chassis, the new BMW Z4 Coupe uses a class-leading safety system to protect occupants. The strong body shell is mated to active and passive systems that offer the driver and passenger the highest levels of safety available.



Dynamic Stability Control +: making the best better

All BMW Z4 Coupe buyers benefit from the most advanced form of traction control available in any production car, called Dynamic Stability Control+ (DSC+). DSC+ builds on BMW's already advanced DSC system that includes Automatic Stability Control, Corner Brake Control and Electronic Brake Distribution. Under slippery conditions, these functions combine, under the banner of DSC, to cut engine power, brake individual wheels and switch traction between the rear wheels for optimum grip.

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