The new car will hit dealers in May next year and will be initially available with three engines: the 2.5-litre 23i, the 3.0-litre 30i and a tuned 3.0-litre twin turbo in the 35i.
The 35i unit is the acclaimed International Engine of the Year and produces 306bhp at 5,800rpm, propelling the car to 62mph in 5.2 seconds and on to an electronically-limited top speed of 155mph.
The twin-turbocharged 2,979cc engine with high-precision direct injection technology produces 400Nm of torque from just 1,300rpm.
Joining this model in the launch line-up are the Z4 sDrive23i and the Z4 sDrive30i. Both use the same magnesium aluminium alloy engine, but with varying capacities.
The 2-.5-litre entry-level sDrive23i produces 204bhp and 250Nm of torque. This equates to a zero to 62mph time of 6.6 seconds.
The sDrive30i comes with a 3.0-litre powerplant offering 258bhp and 310Nm of torque. The six-cylinder engine records a zero to 62mph time of 5.8 seconds.
The new Z4 will be the first to come with a two-piece, electro-hydraulically operated retractable hard-top roof that can be raised or lowered in 20 seconds.
The new roadster will also be the first vehicle to be offered with adaptive M suspension.
Electronically controlled dampers will offer three different configurations and lower the ride height by up to 10mm for a more dynamic drive.
Transmitting the power to the road in all three Z4s is a six-speed manual gearbox as standard. Customers of the Z4 sDrive23i and the Z4 sDrive30i who prefer the characteristics of an automatic can specify a six-speed Sport Automatic transmission featuring gear change paddles on the steering wheel.
Buyers of the Z4 sDrive35i can choose the more advanced seven-speed Double Clutch Transmission, again with gear-shift paddles located on the steering wheel.