Third-gen BMW roadster to rival the Porsche 718 Boxster; range currently topped by 340hp M40i variant.
After revealing design sketches and images of the model having leaked online, the all-new, third-gen BMW Z4 has finally been revealed at the Pebble Beach Concours d’Elegance in Monterey, California. The model’s European debut is scheduled to take place at the 2018 Paris motor show.
As we had known earlier, the Z4 roadster has been co-developed with Toyota’s upcoming Supra and shares its new platform (codenamed G29) with that model. However, the rival to the Porsche 718 Boxster also borrows chassis, suspension and electrical components from BMW’s cluster architecture (CLAR) platform, which is used on models like the 5-series, 7-series, X3, X4 and X5. Incidentally, the upcoming seventh-gen 3-series sedan will also be built on the same platform.
BMW engineers had a brief to make the new Z4 more dynamic in its driving qualities than its predecessor. This has been claimed to be achieved by incorporating extra-wide sill elements that are said to contribute to a more than 30 percent increase in torsional rigidity over the structure used by the older model. During our sister publication Autocar UK’s drive of the prototype, BMW described the new Z4 as the stiffest open-top car the carmaker has built to date, claiming it to be stiffer than even the fixed-roof M4 coupé.
To further differentiate the new Z4 from the second-gen model, a completely new design with more distinctive proportions has been adopted, along with an electrically operated fabric hood. The new structure is claimed to weigh 60kg less than the folding hard-top arrangement of the previous Z4, which also helps to lower the centre of gravity and provide what BMW officials describe as “more sporting driving attributes”.
Despite being larger than the outgoing Z4 (including a 70mm increase in width), the new drop-top is also said to be around 50kg lighter than its predecessor, indicating that the range-topping M40i trim will weigh less than 1,500kg. While the Z4 continues with the front-engine, rear-wheel-drive layout, the motor is placed well back in the engine bay, contributing to a 50:50 weight distribution front to rear. In M40i M Performance First Edition guise, its suspension (a combination of double wishbones up front and a five-link arrangement at the rear) features multi-mode electronically controlled dampers. An M Sport braking system is also standard on this model, as are 19-inch alloy wheels.
The interior of the Z4 features a new driver-centric dashboard with technology borrowed from BMW’s sedans. Along with a new digital instrument display and a touchscreen infotainment system, newly developed seats and a unique set of controls housed within a broad centre console has also been added. The options list on the Z4 is predictably long, and includes a head-up display and a Harman Kardon sound system, both of which are fitted as standard to the M40i M Performance First Edition.
The current top-spec variant of the Z4 is powered by the same 3.0-litre, in-line, six-cylinder turbo-petrol engine found in a number of existing BMWs. With 340hp and 450Nm of peak torque, the M40i M Performance model is claimed to do the 0-100koh sprint in 4.6 seconds and go on to a limited top speed of 250kph. Compared to the second-gen model, the peak power output is actually 3hp less in the new Z4 M40i. However, the M40i M Performance’s 450Nm of peak torque is more than the previous-gen Z4 M Roadster's 365Nm.
The Z4 M40i’s main rival, the 718 Boxster S, is powered by a 2.5-litre flat-four turbocharged unit with 350hp and 420Nm of torque.
There will also be entry-level Z4s in the form of the sDrive20i and sDrive30i, both of which will share a a 2.0-litre four-cylinder turbo-petrol motor. Outputs for the sDrive20i and sDrive30i will be 152hp and 250Nm and 264hp and 390Nm, respectively.
Transmission duties are expected to be carried out by an eight-speed automatic across the range, though the sDrive20i may also get a six-speed manual as an option. While rumours had suggested that all-wheel-drive would be on offer with the new Z4, BMW officialsconfirmed that it will be sold exclusively in rear-wheel-drive form. The M40i M Performance also comes as standard with an electronically controlled rear differential.
BMW is also expected to bring out a version of the Z4 that will, for the first time in the roadster’s history, get proper M treatment. The Z4 M is expected to be powered by the same turbocharged 3.0-litre in-line six-cylinder engine launched in the new M2 Competition that produces 410hp and 550Nm of torque.
While BMW has not revealed plans to bring the all-new Z4 to India as yet, the previous, second-gen model was on sale in our market with a 3.0-litre, straight-six, turbo-petrol engine that sent 306hp and 400Nm of peak torque to the rear wheels via a seven-speed automatic.