Engine

The Z4 is powered by some of the smoothest, most refined engines currently available. The line-up offers five powerplants starting with a 150hp 2.0-litre four-cylinder petrol engine and rising to a 343hp 3.2-litre straight-six ensuring a spread of performance to suit all tastes. All engines offer VANOS variable valve timing technology with VALVETRONIC variable valve opening technology featuring on all 'standard' cars (except the Z4 M Roadster).

Using the 3.2-litre engine that has won category honours five times in a row at the Engine of the Year awards, the all-new BMW Z4 M Roadster is the new flagship model of the range. With 63hp more than a Porsche Boxster S, on-road performance is breathtaking. Capable of a zero to 62mph time of just 5.0 seconds, the Z4 M Roadster goes on to an electronically-limited155mph.

But it is not just the BMW Z4 M Roadster powerplant that has a story to tell. Featuring the world's lightest production six-cylinder engine made of aluminium and magnesium, the BMW Z4 3.0si uses VANOS and VALVETRONIC variable valve technology to help it achieve 265hp and 315Nm of torque - figures which also better the output of a Porsche Boxster. On the road this results in a zero to 62mph time of 5.7 seconds and an electronically limited top speed of 155mph.

The Z4 2.5si and Z4 2.5i Roadsters offer two outputs from the same six-cylinder engine. The 2.5si delivers 218hp and 250Nm of torque and records a zero to 62mph time of 6.5 seconds before going on to a top speed of 149mph. Meanwhile, the Z4 2.5i with its 177hp and 230Nm engine achieves a zero to 62mph acceleration time of 7.1 seconds and a top speed of 142mph.

Representing the entry point to BMW Z4 ownership, the 2.0-litre four-cylinder petrol model is powered by an engine built at BMW's Hams Hall production facility in the Midlands. Using both VANOS and VALVETRONIC technology to develop 150hp and a peak torque of 200Nm, the car is capable of a zero to 62mph time of 8.2 seconds and a top speed of 137mph.

So smooth was this 2.0-litre powerplant in the first generation Z4 that testers from Evo magazine were moved to comment that the car felt the same behind the wheel as a six-cylinder engine. Top Gear magazine was similarly enamoured, referring to the model as a car that made a lot of sense with buyers who get the looks, dynamics and open air motoring of the rest of the Z4 line-up, but with savings on the initial outlay, economy and even on insurance.

The Z4 2.0-litre is also a tax efficient proposition for the company car user courtesy of CO2 emissions of just 181g/km that sees it slip into a lower Vehicle Excise Duty tax banding than other Z4's. An award from Fleet Week and Fleet Management publications, which voted the Z4 their Car of the Year, only serves to back-up the roadster as a credible company car choice.
 

Transmission

All the new Z4's come as standard with a six-speed manual gearbox and this short-shifting 'box is the sole transmission available on the M Roadster. A new 'Sport Automatic' gearbox, optional on 2.5si and 3.0si six-cylinder Z4's, offers a full auto mode or the option to change gear using the gear stick or paddles located behind the steering wheel. A 'Sport Automatic'-equipped car not only changes gear faster compared to the previous automatic gearbox offered on the original Z4 but blips the throttle on down-changes for a smoother transition between gears.

This is the first use of paddles on a BMW automatic transmission system. All previous Sequential Manual Gearbox (SMG) systems, as the name suggests, were based on a manual 'box. Drivers of the Z4 2.5i can also specify the same automatic transmission offered previously in the original Z4.


Chassis

One of the stiffest chassis in its class provides the Z4 with the perfect basis on which to engineer a sportscar with supreme on-road dynamics. With kerb weights in the range between 1,295kgs and 1,485kgs - lighter than comparable cars from Audi, and Mercedes - and a low centre of gravity, the Z4 range offers true driving pleasure.

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