By LAWRENCE TAN

BMW has unveiled the next generation of its classic roadster, the 2010 BMW Z4, set to replace the existing convertible and coupe models, and a world debut in Detroit next month.

Gone is the soft-top roof in this iteration, replaced by a retractable aluminium hood that opens and closes in 20 seconds. BMW says with the hood up, the storage space increases from 180 to 310 liters. 

Otherwise, the new Z4 sports larger and wider kidney grilles, and overall, features simpler and more elegant lines compared to its predecessors.

There's a choice of three engines, distinguished by BMW’s newly adopted and somewhat tricky nomenclature, for the new Z4.

The range-topping Z4 sDrive35i houses the twin-turbo 3.0-liter inline six (302bhp, 295lb-ft of torque), which claimed the International Engine of the Year award this year, and also features across other BMW models like the 7-series, 3-series, and X6.

A 0-62 mph sprint takes 5.2 seconds, and those who opt for the seven-speed double clutch transmission get to accomplish the same feat in 5.1s.

The entry level Z4 sDrive23i gets a 2.5-liter straight six with 204bhp, while the middle child sDrive30i settles for a non-turbocharged inline six 3.0-liter with 258bhp.

The standard cockpit feel of the new Z4 is enhanced with wood and leather accents aplenty. iDrive makes its debut in the Z4, having first featured in the new 7-Series. There’s also a 9-inch LCD display that emerges from the instrument panel.

The new Z4 is expected to be available starting May 2009, priced between 35,900 euros and 47,450 euros.

BMW