Today's BMW Z4 has even more attitude than before. Jonathan Crouch takes a look.
Ten Second Review
BMW knows a thing or two about roadsters and this improved second generation Z4 is one of its best. It may not be the sharpest car in its class to drive but on the right day, in the right mood on the right road, you may not care, providing you're a fan of metal-folding roofs. The engines are efficient and willing, the looks are still stunning and the feeling you get behind the wheel still makes you feel twenty years younger. Maturing extremely well, this, it seems, is a Z that remains very hard to catch.
So, to this improved version of BMW's second generation Z4 roadster. Back at its original launch in 2009, the Munich maker set itself quite a challenge with this car. After all, the company's marketing stance as builder of 'the ultimate driving machine' seemed unlikely to be underlined by equipping its affordable roadster for the first time with a heavy folding metal roof. Yet that's exactly what we got in a car that in its segment sits somewhere between the elegant cruiser that is Mercedes' SLK and the sporting appeal of a Porsche Boxster. Now it's smarter, faster and more efficient, plus there's a lower-powered entry-level sDrive 18i variant to make it more affordable. That metal-folding roof tells you a lot about BMW's target market for this model. If it had been gunning primarily for Boxster buyers, then the Bavarians might have been able to resist the fashionable demand for automotive metal tops that flip down like Swiss army knives. As it was, they felt that the Z4 simply had to have one to properly compete. And as usual, their design team did the best possible job with the tools available. By early 2013 though, newer rivals were stealing the limelight in the roadster sector, hence the introduction of this updated model. A car we're going to put to the test.
Sporting BMWs may have been inseparably associated with six cylinder engines down the years but most of the powerplants on offer in this improved Z4 line-up squirt fuel into the quartet of cylinders boasted by a TwinPower Turbo 2.0-litre unit that's offered in three states of tune. The 184bhp sDrive 20i and 245bhp sDrive 28i variants are carried over from before but in an attempt to snare customers who might otherwise have to settle for cheaper segment rivals like the Mazda MX-5 or the MINI Roadster, BMW has introduced a more affordable Z4 starter model in the form of the 156bhp sDrive 18i we tried. If you want more, the two 3.0-litre in-line twin turbo six cylinder models, the 306bhp sDrive 35i and the 340bhp sDrive 35is, are respectively able to demolish the 0-62mph sprint in 5.2s and 4.8s. In contrast to Audi and Mercedes, BMW doesn't think you'll want a diesel option. All Z4s come with BMW's Drive Performance Control system. Here, via focused 'Sport', efficient 'ECOPRO' and relaxed 'Comfort' settings, you can set your car up to your own preferences, just like a race team would on a racecar. That means altering the response of throttle, steering, stability control and even the gearchange times if you've opted for the eight-speed automatic or the full-blown M DCT 7-speed twin-clutch auto transmission that's the only choice for sDrive 35is buyers.
Design and Build
Four wheels, two seats and a big engine. It doesn't get much simpler than that. Like any classic roadster, more than half the length is given over to the engine, which is one reason why there's only space enough for a couple of passengers. As to the changes made to this revised version, well, they don't amount to very much. The headlights now include white LED corona rings and a white 'eyebrow' with additional chrome detailing, while in profile, the side gill features chrome detailing and LED side repeater lights. Neat detailing then - and neat packaging too. You'd certainly expect the inclusion of a two-piece electro-hydraulic metal-folding roof to have altered this Z4's appearance a good deal more than it has but there are no awkward looks, no tell-tale bulky rear end. BMW's design team could work miracles though and in return for the security of a hard top, you've to accept a couple of significant drawbacks. First, the speed of operation: this top takes around 20s to raise or 21s to lower (about twice as long as the roof on a fabric-topped Audi TT Roadster). At least you can operate it at speeds of up to 20mph though. The other issue, rather predictably, concerns bootspace. That's fine of course when the roof's up - with 310-litres on offer. When the top's retracted though, that figure falls to just 180-litres - about 25% less than you'd get in a rival Mercedes SLK.
Market and Model
List prices suggest that, allowing for a few well-chosen extras, you'll probably be paying somewhere in the £28,000 to £46,000 bracket for your Z4. Almost all BMW's business here is done with the four cylinder 2.0-litre petrol engine that powers the sDrive18i, 20i and 28i variants, leading to an average Z4 purchase price in the £30,000 to £35,000 bracket. There's a £5,000 step up from that if you want one of the 3.0-litre six cylinder models, priced in the £40,000 to £45,000 bracket. If, having considered all of this, you conclude that it is a Z4 that you really, really want, then you're going to want to know what BMW includes in the standard equipment tally. And the answer is a reasonable amount. As well as the power folding roof and Drive Performance Control, buyers of this entry-level sDrive18i get 17" alloy wheels on run-flat tyres, Xenon headlights with daytime driving lamps, a Thatcham Category 1 alarm, a proper heated rear window, a multi-function leather-trimmed sports steering wheel, a BMW Professional stereo system with DAB digital radio plus USB and aux-in inputs, Bluetooth 'phone compatibility and a trip computer. It's hard though, here at the bottom of the Z4 line-up, not to focus on what you have to do without. After all, if you add the leather trim, air conditioning, auto headlamps and rain-sensing wipers that all other Z4 models get, you get within £400 of the pleasingly more powerful sDrive20i variant.
Cost of Ownership
These days, even barnstorming sports cars need to keep running costs in check while treating the environment with kid gloves. The Z4 does a better job of this than you'd credit for a car in such a lofty performance bracket, mainly thanks the BMW's EfficientDynamics programme. Thanks to this, assuming you keep an eye on the optimal gearshift indicator, you should be able to get somewhere close to a combined cycle fuel figure which for the four cylinder engine is quoted at 41.5mpg, whichever state of tune you order it in - sDrive18i, 20i or 28i. These figures are also identical to those of rival Mercedes SLK 200 and Audi TT Roadster 2.0 TFSI models. If you're shopping at the upper end of the Z4 four cylinder line-up, the prospect of an sDrive28i model capable of getting to 62mph in around 5.5s yet, with restrained use still able to return over 40mpg, is a tempting one. As for the six cylinder models, well it might be a little surprising at first glance to find that the 340bhp sDrive35is actually out-performs the 306bhp sDrive35i, but that's because the flagship variant comes only with the more efficient 7-speed DCT paddleshift auto transmission. With this installed, the sDrive35i's returns - 30.1mpg and 219g/km - are marginally improved to 31.4mpg and 210g/km. That's still some way off what you'll get in a rival Mercedes SLK 350 though.
BMW has been building roadsters for over 80 years - and it shows with this improved second generation Z4, a model that's matured extremely well, slowly and methodically developing into an all-rounder that's tough to beat. In fact, I can't help feeling that this is probably the ideal car of its kind for most potential buyers. True, it isn't the driver's machine that, say, a Porsche Boxster can be but it gets close enough for many likely customers to start prioritising the lower pricing and security-minded metal folding roof that come with this BMW. As for the most recent changes made to the line-up, well, slotting in an affordable model at the entry-level point has certainly kept the Z4 relevant to customers with tighter budgets and while 156bhp might not instantly bring to mind an 'Ultimate Driving Machine', even that sDrive18i variant has enough about it to entertain. Further up the range of course, power is plentiful and if you like your aural fireworks, the in-line six cylinder variants sound glorious. What it all means is that though the Z4 might not be the first car you look at when choosing a sports roadster, look at it you must. It's now just too good not to.