MAKE IT OR FAKE IT

Looks and sound come up short but a sporty drive lurks within the Z4 roadster

Style is core to the appeal of a convertible sports car. So the responsibility shouldered by Sydney’s Calvin Luk was enormous when designing the third-generation of BMW’s Z4 roadster. Originally shown in concept form at the exclusive Pebble Beach classic car show last year, Luk’s first draft won favour with its long wheelbase, cropped windscreen, stretched bonnet and short overhangs, taken from the textbook of how to make a beautiful roadster.

But the production version now on sale lacks the same impact.

There are good reasons. Its shorter wheelbase brings improved agility, taller customers need the wind protection provided by deeper glass and increasingly stringent crash test requirements for pedestrian protection compromise front-end styling.

Looks apart, those who fall for its charms can choose from three versions of the Z4, a pair of four-cylinders in the sDrive 20i and 30i plus a six-cylinder hero variant in the M40i.

Priced from $84,900, the basic Z4 comes with 18-inch alloys, sports suspension and an eight-speed automatic transmission for its 2.0-litre turbo (140kW/320Nm).

You get dual-zone climate control, 10-speaker audio, BMW’s latest digital dashboard with a year’s subscription to Apple CarPlay, wireless smartphone charging and head-up display.

The cabin is more liveable than before, with improved seat space, extra storage and a digital

dash layout that is genuinely clever yet retains knobs to adjust the audio and climate control.

You can subscribe to digital services that allow some smartphones to serve as keys — even granting temporary access to friends and family.

Mid-spec 30i models on sale from $104,900 get 19-inch wheels, adaptive suspension, LED headlights, active cruise control and bigger brakes to rein in the 190kW/400Nm outputs.

At the top of the pile, the $124,900 M40i brings a 3.0-litre six-cylinder turbo (250kW/500Nm) as its main feature, along with a sports differential, 12-speaker audio, ambient lighting and further fine-tuning.

As ever, BMW’s inline six is a magnificent creation. Smooth and sonorous, the engine soars throughout its rev range with flexible wallop that makes it a joy to drive.

BMW reckons it’s good for a 0-100km/h sprint in 4.5 sec, more than two full seconds faster than the base version.

Engineers tuned the machine at Germany’s Nurburgring circuit, where the M40i is quicker than BMW’s M2 performance coupe.

The big six has a fine partner in the eightspeed automatic with driver-adjustable modes and paddle-shifters, along with a carefully programmed “whomp” from the tailpipes as you accelerate through the gears.

Less impressive are the four-cylinders, which bring fake sound effects and the potential to be embarrassed by hot hatches.

The Z4 has weighty if numb steering and rear-drive playfulness but these are compromised by overly stiff suspension that even in its plushest settings never feels settled on broken roads.

Lacking the finessed composure of wellsorted performance cars such as Porsche’s 718 Boxster — or, again, some hot hatches — the Z4 can feel brittle or bouncy on the road. Of the trio, the M40i is the most convincing, whether driven hard or at a cruise. It’s properly quick and more engaging than before.

After all, if a sports car doesn’t look stunning, it should at least be fast and fun to drive.