This test mule wears heavy disguise, but the overall shape can be viewed showing it retains the familiar set-back cabin, pert rear-end and long bonnet. The kidney grille looks to be larger than ever, although the visible light designs are fakes.
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BMW has ditched the current Z4's heavy metal folding roof for a lighter, more traditional fabric hood. This could mean it is being aimed more towards the Porsche Boxster and away from softer, more refined cars like the Mercedes SLC. The soft-top will gain a rear-window for production.
An insider told us in 2014 that “this car will use the same lightweight body construction as the i3 and i8. And even with that type of construction, you can expect a price around the same as that of the current Z4."
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BMW, which could receive a new 'Z5' nameplate to help differentiate it from today's car, is being developed in part with Toyota. The Japanese brand is likely to use the platform for it's own sports car of similar design. Rumouras suggest it could bring back the iconic 'Supra' name.
The Toyota version has potential to receive a plug-in hybrid model, with electric motors boosting output instead of a turbocharger. BMW should stick to its tried-and-tested 'Twinpower' forced induction, but there's potential for future crossover.
We could even see a turbocharged three-pot offered, borrowed from the new 3-Series. And don't be surprised if BMW's M-Division get involved later on for a new Z4 M.
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