The development of the new BMW Z4 – set for launch at the Paris Motor Show – possibly was one of the most interesting projects the Munich carmaker undertook in recent times. FERDI DE VOS reports on the revitalisation of the Bavarian roadster.
Zukunft, the German word for future, and is represented by the ‘Z’ in BMW’s line of roadsters that, up to now, has been produced in four different series covering five generations.
With the launch of the third generation Z4 at the 2018 Paris Motor Show (after it was previewed at the Pebble Beach Concours d’Elegance in the United States), the Bavarian automaker hopes to secure the future of its roadster line-up.
See, while BMW may have a rich history of roadsters that have stood out as icons of pure driving pleasure, these cars had varying success in the marketplace. Munich’s unpleasant experiences with models such as the achingly beautiful, but overpriced 507 (no roadster was built after this model for thirty years), the limited production Z8 and the interesting, but ultimately unviable Z1, made it wary of this segment.
Roadsters, in general, are notoriously expensive to produce, and it is hard to justify the development of such a niche model in strict business terms. However, the success of the Z3 and the first generation Z4 made it possible for BMW to continue the modern roadster tradition started by the Z1 nearly thirty years ago, in 1989.
Flailing sales later in the life cycle of the second-generation E89 Z4, the first Z Series model to use a retractable hardtop, did put the future of the roadster models in jeopardy, but an unexpected twist of events brought much-needed relief.
Japanese giant Toyota, to rekindle its long-lost legacy of performance cars, was keen to develop a new Supra, while BMW wanted a new Z4. So, why not pool the two brands’ extensive resources? An agreement was reached, and development on the G29 Z4 and fifth generation A90 Supra started in 2013.
PARALLEL DEVELOPMENT
It would seem, however, that the term “joint development” by BMW and Toyota may be a stretch of the imagination, as, according to reports, the Z4 and Supra teams cut all ties in 2014 and carried on working in parallel.
Recent reports suggest that the program assistant chief engineer for the Supra, Masayuki Kai, in an interview with CNET at an event in Spain (where the new Supra was introduced, still clad in its development camouflage) said his team had not shared any development details with BMW in four years. According to him, the sides agreed on packaging and then went their separate ways.
Be that as it may. What matters is that BMW indicated its new two-seater had been systematically designed for agility, dynamism, and supremely precise steering characteristics with instantaneous response, and that the car’s proportions provide evidence of how the classic roadster concept has been reinterpreted.
Compared to its predecessor, the latest Z4 is 85 mm longer (4,324 mm), 74 mm wider (now 1,864 mm) and 13 millimetres taller (1,304 mm), but interestingly it has a 26 mm shorter wheelbase (now 2,470 mm) and a wider track – 1,609 millimetres at the front (+ 98 mm) and 1,616 millimetres at the rear (+ 57 mm).
BMW states that the shorter wheelbase serves to sharpen agility, as do the notably broader tracks, while a new design for the front and rear axles gives the car a sportier edge; at the same time guaranteeing high comfort levels.
The body structure and chassis mountings have remarkably high rigidity, according to the Bavarian manufacturer, and the central seating position, low centre of gravity, minimised weight and ideal 50:50 weight distribution further contributes to the dynamism of the new Z4.
NEW DESIGN LANGUAGE
The premium open-top sports car – which has reverted to a classic electrically-operated fabric soft-top that can be raised or lowered in 10 seconds at speeds of up to 50 km/h, instead of its predecessor’s retractable hardtop – has a low-slung, sporty and compact appearance.
Besides a new, wide mesh-design kidney grille, the Z4 has – for the first time – a vertical headlight arrangement with a slight Jaguar F-Type feel to it. LED lights are standard, and Adaptive LED headlights with matrix function for the non-dazzling high beam and cornering lights are optional.
The long bonnet boasts arrow-shaped contour lines directed at the grille, while the joins at the bonnet’s sides merge into the upper character line running all the way back to the tail lights. A second character line emerges from the large Air Breather rearwards of the front wheel arch.
The boot lid has an integral spoiler, while slender L-shaped light units and a diffuser gives the rear a muscular look.
The driver-focused cockpit has clear lines with dynamic élan, and electroplated detailing adds to the roadster’s elegant presentation, with the well-structured controls arrangement focussed on enhancing the driving experience.
Model-specific sports seats with integral head restraints are either upholstered in Vernasca leather, or leather and Alcantara, with the optional draught stop fitting flush between the rollover bars.
The display and operating system have also undergone improvement, and the roadster is optionally available with BMW Operating System 7.0, with state-of-the-art digital functions, while BMW Live Cockpit Professional brings customisable graphics to the fully digital instrument cluster and control display.
There is storage space behind the seats, and luggage capacity is 281 litres with the soft-top open or closed – over 50% more compared to the outgoing model.
MIGHTY ENGINES, ENHANCED CHASSIS
The Z4 uses BMW’s modular Cluster Architecture (CLAR) platform that incorporates steel, aluminium, and carbon fibre, and while stiffer the new model is up to 50 kg lighter compared to its predecessor.
The suspension comprises a newly designed double-joint spring strut axle at the front and a five-link rear axle, giving the Z4 a good balance between sportiness and ride comfort, while variable sports steering with both power assistance and steering angle adjustment helps precision in corners.
The engines available for the new Z4 have benefitted from multiple detail upgrades. The flagship and poster child Z4 M40i is endowed with a 3.0-litre straight-six unit with M Performance TwinPower Turbo technology. It delivers 250 kW and peak torque of 500 Nm – enough to, according to BMW, propel the roadster from zero to 100 km/h in an impressive 4.5 seconds.
With this kind of power delivery available from an M Performance model, it is highly unlikely that Munich will again introduce an M Roadster version, such as in the Z3 line-up (the first Z model to have this high-performance variant) or the first generation Z4. It also seems unlikely that BMW will develop a Coupe version of the new Z4 – even though the Supra is a Coupe,
A pair of 2.0-litre four-cylinder units completes the engine line-up with the variant in the sDrive30i delivering 190 kW of power and 400 Nm of torque. This enables it to sprint from zero to 100 km/h in 5.4 seconds. In the sDrive20i, maximum output is 145 kW and peak torque 320 Nm, translating into a sprint time of 6.6 seconds.
The engines all have particulate filters to reduce emissions, and power is delivered to the road through the latest-generation eight-speed Steptronic Sport transmission. No manual versions will be available.
The top-line M40i also has adaptive M Sport suspension, M Sport brakes, and an electronically controlled M Sport differential, while a selection of drive modes (Comfort, Sport or Sport+) noticeably changes the car’s responses and behaviour.
An array of driver assistance systems further underlines the advanced character of the Z4. Collision Warning, Pedestrian Warning with City Braking function, and Lane Departure Warning systems are standard, while options include Active Cruise Control with Stop & Go function, and – for the first time in a roadster – a Head-Up Display.
LAST WORD
Perhaps the detached development (if true) of the Z4 and Supra will have positive outcomes for both. What is clear so far is that the new BMW Z4 now combines powerful performance and sporty on-road prowess with a wealth of advanced, top-class equipment features on the driver assistance, operation and connectivity fronts.
Given these attributes, market reception of the revitalised roadster – when it arrives here halfway through 2019 – should be good, securing the Z Series’ existence for the foreseeable future.
Report by FERDI DE VOS | Images © BMW AG