Zed’s not dead Z4 M40i
WE SAY: IS IT A ROADSTER? OR A SPORTS CAR? BOTH, SAYS BMW. LET’S FIND OUT...
Folding hard tops were invented when soft tops were too easily penetrated by the weather and vandals with Stanley knives. These days, a well-done fabric roof really is all you could want for cosiness, and the yobs are too busily engaged in socialmedia bullying. So the new Z4 wears a cloth cap.
So if there’s no hard top under there, I wondered aloud to a designer, why’s the tail so bulky? I kept silent on my opinion that it’s unbecomingly so. Aerodynamics is the answer I was given. At the other end of the car, the jutting jowls are designed to help capture airflow and usher it past the wheels. If you don’t like it, lower-spec Z4’s have a slimmer front bumper. Whatever the reasons, a measure of gawkiness afflicts the proportions of this coachwork. Shame. You want it to be handsome because, more than any other kind of car, a roof-down roadster is an item of clothing.
Not just a roadster but a sports car, the BMW engineers keep saying. They quote a Nürburgring lap time. La-la-la... I’ve stopped listening since they told us a time for the 2-Series Active Tourer minivan. Oh hang on, the Z4 M40i time is under eight minutes. Its physical dimensions are good for lappery
– a shorter wheelbase than before by a huge 20cm, for agility; a much wider track, for grip; a lower centre of gravity. The body is a whole lot stiffer than the old Z4’s, and it’s light, aided of course by ditching the powered hard top. The front suspension, unlike other BMWs,
mounts to a special aluminium subframe for precision. Those aren’t the only declarations of intent. The Z4 M40i’s tyres come from the M4. There’s an e-diff between the rear halfshafts. You get the gist.
Six cylinders too. When Porsche’s roadster has just the four and Audi’s five. Mercedes does six, but they’re in a V not inline, and live in an SLC. So that’s a win for Munich. Mind you, for another £10k you can have a V6 supercharged Jaguar F-Type roadster and you can order the Jag with a manual. There are a whole three of those on AutoTrader as I write, versus 200 of the automatic versions. The Z4 doesn’t permit you the choice of that resale-suicide manual transmission. The Z4 M40i that we’re driving here, by the way, tops off a range that begins with a pair of what are now BMW-staple 2.0litre fours, the 30i and 20i.
The M40i revs to 7,000rpm, and all the sensations – in the pull of it and the sound of it – say it’s pretty darned chuffed to be doing so. You can wring the best out of it by using the shift paddles and watching the revs, but BMW makes it hard for you because the newly designed virtual instrument panel (common to the new X5 and 8-Series, and upcoming 3-Series too) has a hopelessly illegible tacho and tiny gear indicator. I’ve banged on about the graphics of that cluster before, and familiarity has in no way bred content.
Anyway, here we are, cracking along, enjoying the six-cylinder’s generosity. The chassis can easily cope. As promised, there’s enormous grip, and the suspension keeps a vigilant eye on body roll and float. The steering is high-geared – gets even more so on lock too – but it acts intuitively so you can always aim the car with lovely accuracy, and even small efforts will thread it into a tight bend with the immense forces those tyres can generate. Only thing is, you don’t get a whole lot of sensation back from the front wheels. That job is left up to the back end. You feel the e-diff working as you lean onto the power, the rear half of the Z4 crouching down and neatly holding onto the edge of traction as it bleeds out of a bend.
The engineers say that at the start of the project they used the M240i as a handling benchmark, but soon realised that they’d be insulting themselves if they kept their aim there. So the target became the M2. I don’t think the Z4 is quite that transparent, but it’s that capable, for sure.
“BMW is one of the global holdouts for straight-six engines and rear drive”
The M2 has passive dampers, and their emphatically judged calibration, especially in the Competition version, is why the M2 is so captivating when you’re driving in fully recreational style. And why it’s jiggly the rest of the time. The Z4, by contrast, has adaptive dampers, with two programmes. Even in the sport mode, where you get clearly sharper turn-in, they allow the suspension to relax a certain amount on the straights. In Comfort, things really become remarkably supple, rounding off most of what a broken surface throws at it. So the
Z4’s chassis relaxes nicely into commuting or long-haul work. And while you’re at it, the driver aids and connectivity are as hygienic as you’d expect from modernGerman premium.
Roof-up at motorway speed, there’s a mildly turbulent hiss of rushing air, but otherwise its insulation, warmth and general stormproofing are beyond serious reproach. Spend 15 seconds pressing a button to lower the cloth but keep the windows up and the neat little wind-blocker in place. That way you can still enjoy the excellent stereo at speed. Even on a parky day there’d be no call for one of those airscarf gadgets.
Of course the soft top is important for another reason. It separates the Z4 from the Toyota Supra coupe. Ah yes, you can thank Toyota for the existence of the Z4. Six years ago, BMW phoned the Japanese because it was looking for fuelcell expertise. Toyota took the call because it figured on swapping that for the Germans’ skills in cutting weight, and in making carbon fibre more cheaply, and in lithium-ion battery cell chemistry. So far, so industry-dull.
But then the engineers got talking about a sports car. Because who wouldn’t? Toyota wanted a new Supra but didn’t have a platform. BMW saw the roadster market softening and wasn’t sure if it could sell enough to justify replacing the Z4. Together, though, they might just make a sensible business of it. BMW of course is one of the staunchest global holdouts for straight-six engines and rear drive, two articles of faith for a Supra.
The basic engineering of the Supra is BMW, the engine most conspicuously. The two sports cars’ suspension and basic platform parts, and the electronics too, come from BMW’s current set that’s used on every longitudinal car they’ve launched since the 7-er of 2017. The Supra is tuned and set up differently from the Z4, but the Z4 people tell me that this work was actually done largely by BMW techs to Toyota’s instructions. Both the cars are built at a BMW-overseen line in the Magna plant in Austria (the same place that builds certain 5-Series plus all Jaguar I-Paces and E-Paces, and the Mercedes G-Wagen, fact fans).
So if it matters to you that a car has ‘brand purity’, you’ll be wanting the Z4. If you want a roadster, that’ll also be the Z4. The Supra, a coupe, plays to a different, JDM-infused, vibe. So despite the common rootstock, these cars legitimately appeal to different audiences. Meaning more sales overall, which is the whole point, innit.
The roadster – perfect for the long, wet winters of the UK
Cabin doesn’t need that fancy airscarf business as it’s well stormproofed