BMW has unveiled the next generation of the Z4 roadster ahead of its world debut at the Detroit Motor Show which start in January 2009. The styling and proportions are classic roadster with long hood, short overhangs and broad shoulders intepreted with modern styling elements such as integrated LED indicators on the flanks as well as headlights and tail lamps.

Image Courtesy: Autoblog

The new Z4 roadster features an aluminium roof which opens and closes down in 20 seconds. Its more airy too with 40% larger side windows and 52% larger rear windows than the outgoing soft-top model. The new model is larger outside overall compared to the predecessor, 5.8 inch longer, 0.4 inch wider and 0.3 inch lower with a wee-bit longer wheelbase, resulting in more room and comfort for the passengers.

The powertrain options include a 300 bhp twin-turbocharged 3.0 Litre V6 in the sDrive35i and 255 bhp naturally aspirated version of the same engine in the sDrive 30i variant.

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The most impressive aspect of the forced inducted engine is the flat torque output of 300 lb-ft from low 1,400 to dizzy 5,000 rpm! The 300 bhp engine makes the sDrive35i accelerate from 0-60 mph in a brisk 5 seconds while the naturally aspirated engine does it in a not so slow 5.6 seconds.

Both the variants can be had with either a manual transmission or optional sport  automatics. The Z4 sDrive35i is available with a 7-speed dual clutch automatic while the lesser powerful Z4 sDrive30i comes with a 6-speeder. The driver has the option of a fully automatic gear selection or manual shifting by means of the paddle shifters on the steering wheel.

The new Z4 Roadster also comes with BMW’s Dynamic Drive Control which let the driver choose between one of the three suspension and drivetrain settings at the touch of a button and a new electronic rear brake management system that emulates a ‘limited slip differential’ for stronger acceleration in turns.

The optional sports package adds Adaptive M suspension and electronic damping control. In addition, the Dynamic Driver Control also varies the reponse of the aceelerator, power steering and threshold of the stability control programme in accordance with one of the three modes - ‘Normal’ ‘Sport’ ‘Sport+’

17 inch lighweight lloys with runflat tyres and tyre pressure monitoring are standard in both the models. To balance out performance and efficiency, BMW’s EfficientDynamics technologies include on-demand management and control of car’s accessory drives, intelligent lightweight technology, variable oil pump and fully optimized aerodynamics.

The insides are swathed in leather with the option of 3 trim colors plus the optional Ivory White Nappa leather trim as a part of an exclusive package. A total of 9 color options are on offer including a roadster exclusive Orion Silver Metallic.

BMW’s latest iDrive system also makes its appearance for the first time in Z4 with a generous 8.8 inch screen and integrated navigation. A spacious 80 gigabyte hardrive stores navigational data and has 15GB of storage space available for your music.

The new Z4 will be built at company’s Regensburg plant in Germany alongside the 3-Series and 1-Series models.

Gallery: 2010 BMW Z4 Roadster