BMW Z4 M40i Roadster (2019) review
There's a new BMW Z roadster in town, and the Z4 M40i range-topper is taking the fight to Porsche.
Shane O' Donoghue
Shane O' Donoghue

Published on November 6, 2018

Will 2018's epic summer mean more convertibles and roadsters sold in Ireland? Unlikely, which means the capable new BMW Z4 will be a rare sight on our roads. Which is a shame, as, in range-topping M40i guise, it squarely takes aim at the mid-engined Porsche 718 Boxster...

In the metal

This new BMW Z4 is a colour, wheel and specification sensitive thing - and I don't necessarily think that the finish of the test cars at the launch showed it off to its best, either. This M40i version is what BMW calls an M Performance Vehicle, so it gets lots of Cerium Grey detailing to differentiate it from the Sport and M Sport variants further down the range, along with a gorgeous set of 19-inch rims and uniquely styled exhaust outlets out back. All versions get LED lighting all-round, including unusually-shaped headlights either side of a new take on the BMW kidney grille, which features an odd mesh insert. The side view includes protruding air outlets behind the front wheels and a pleasingly raked windscreen. We reckon its best angle is the rear three-quarters, which emphasises the chunky back end and all-square stance.

Inside, seating is for two only, with a little storage behind. Leather-trimmed sports seats are standard across the board, as is the BMW Live Cockpit Professional dashboard with two 10.25-inch high-res display screens. The first takes the place of analogue instruments in front of the driver and alters slightly depending on driving mode, though the actual positions of the 'needles' are hard to see at a glance. Still, the way the satnav map is rendered behind the dials is lovely. It's worth investing in the optional head-up display, though. The second display is a touchscreen mounted in the middle of the car, featuring BMW's latest operating system, as launched in the new BMW X5 and BMW 8 Series. It crisply responds to touch and there's voice control, but we still find the rotary iDrive controller to be the best way to use this system on the move.

As in the 8 Series, the Z4's climate control interface is deliciously minimal, tactile and easy to use on the move. That frees up space on the centre console for storage, which is just as well, as it's at a premium. The boot carries 281 litres of luggage (the roof position has no effect on it), which is about normal in this class.

To reduce weight, complexity and the Z4's centre of gravity, BMW ditched the previous Z4's folding hardtop in favour of an automatically retracting fabric roof. It's not quite as good at keeping wind roar at bay, but it looks well and can be upgraded from standard black to a silver fleck appearance. For the record, it goes up or down in about 10 seconds (at speeds of up to 50km/h), either from the key fob or using a centre console mounted button. A rickety wind deflector is optional and fits between the roll hoops at the back of the cabin.

Driving it

We'd encourage Z4 buyers to pay for that deflector, however, as the cabin is remarkably blustery with the roof down, especially if you've lowered the side windows too. You'll want to do that as often as possible in the M40i variant to hear the engine doing its thing. This is the only version of the Z4 (so far) that comes with a six-cylinder engine and it's simply glorious, turbocharger or not. You can read how fast it is in the Tech Specs box above (in summary: very), but enjoyment of it goes much deeper than that. It rumbles at low speeds with promise, purrs along on a cruise and then turns banshee when you explore the upper reaches of the rev counter.

Not that you ever strictly need to do that to make good progress, as there's huge torque on tap across the rev range and the (recently updated - as excellent as ever) eight-speed auto has been cleverly calibrated to make the most of it. Of course, the driver can take full command of the gear-changing if they wish or can just override the system for a short period of acceleration and then let the electronics resume control.

Anyone could jump into the Z4 and drive relatively quickly, safely. The electronic stability control is quick-thinking and though you sense the power going to the back axle when exiting a wet junction, for example, the Z4 doesn't feel unruly in its default settings. However, BMW has ramped up the experience in Sport Plus mode to appeal to those that really love driving. The throttle and transmission respond more quickly, the steering follows suit (it's a variable power assistance and ratio system across the range) and the adaptive damping (standard on the M40i) adjusts its baseline. On top of all that, there's an active rear differential for this version, with characteristics mapped to the driving modes. So, in Comfort, it helps with stability and traction without relying on power-sapping traction control, but in the Sport Plus mode, it helps the Z4 feel even more agile, actively helping the front-end bite hard and rotating the rear in a manner that keen drivers will adore. Yet it feels controlled, too, meaning you can enjoy pushing the car to its limits in the right conditions (preferably a track, in truth) without fear of it spitting you off the road. This Z4 is undoubtedly the best-handling BMW Z roadster yet.

What you get for your money

While the M40i version is arguably worth the money for its upgraded chassis and that sublime six-cylinder engine, the good news is that Z4 ownership starts at a much more palatable €51,762. That's for the entry-level Z4 sDrive20i, powered by a 197hp/320Nm turbocharged 2.0-litre petrol engine. The sDrive30i uses a more powerful version of the same unit, making 258hp and 400Nm of torque. Both of those are offered in Sport and M Sport guises, while the Z4 M40i is a trim level in its own right.


Rear-drive roadsters may be thin on the ground in Ireland, but they're often what car enthusiasts' dreams are made of, and the new BMW Z4 M40i is certainly good enough to keep the keenest of drivers interested with a heady blend of performance, handling acuity and contemporary technology. Still want that Boxster?


Tech Specs

Model testedBMW Z4 M40i
Pricing€75,165 as tested; Z4 starts at €51,762
Engine3.0-litre turbocharged straight-six petrol
Transmissioneight-speed automatic, rear-wheel drive
Body styletwo-door, two-seat roadster
CO2 emissions168g/km (Band D - €570 per annum)
Combined economy38.2mpg (7.4 litres/100km)
Top speed250km/h
0-100km/h4.6 seconds
Power340hp at 5,000-6,500rpm
Torque500Nm at 1,600-4,500rpm
Boot space281 litres
Rivals to the Z4 M40i Roadster (2019)