Spied:BMW Z4

These latest spy shots of the 2009 BMW Z4 caught testing in Germany clearly show that the new two-seat roadster will be getting a folding metal roof in place of the current car’s fabric item.

The next Z4 will make its debut at the LA motor show in November before going on sale in the last quarter of next year.

Aimed squarely at the Audi TT, the new Z4 will come with a comprehensive range of engine, all common to 3-Series on which it’s based.

We’re expecting that line-up to include a twin-turbo 3.0-litre petrol six and the mighty 4.0-litre V8 from the M3. Sources inside Munich also confirm that, for the first time, BMW is almost certain to make a diesel-powered version of one of its ‘Z’-cars, aimed squarely at the Audi TT TDI.

The diesel motor is likely to be the exceptional 204bhp version of the 2.0-litre twin-turbo diesel that is fitted to the 123d Coupe.

The new Z4 will also benefit from BMW’s EfficientDynamics programme, boosting fuel economy and cutting emissions. This is likely to include stop-start and a part-time alternator.

Our pictures of this lightly disguised Z4 show more of its body than we’ve seen before. The looks have been toned down compared with the current car - particularly around the front-end, which is neater and more elegant than its predecessor.

As a result BMW will be hoping for more success with this Z4, which never managed to match the Z3’s peak sales figures in the UK.

The outgoing Z4 peaked in 2004, when BMW shifted 4800 to British buyers – less than half the number of TTs that Audi sold. The current model’s ‘awkward’ styling alienated many buyers, particularly women, who didn’t take to Chris Bangle’s outlandish design.