The pokiest BMW Z4 doesn't wear an M badge but it's still ferociously fast. Jonathan Crouch reports on the sDrive35is
Ten Second Review
The latest generation BMW Z4 has taken some time to really get into its stride, but when you look at the constituent parts of the current car, it's a real knockout. It looks great, drives well, is genuinely efficient and is still very quick indeed in top sDrive35is guise.
BMW is not a company that tends to embrace compromise, but the second generation Z4 is a car that has learned to live with balancing its dynamic talents against commercial expediency. It'll never be quite as elegant a cruiser as a Mercedes-Benz SLK and it'll never quite match the sporting appeal of a Porsche Boxster. Still, what it does - and does extremely well - is offer a halfway house between these two extremes. So you get a folding hard top roof and pretty clever handling to boot. As a car to live with day in, day out, it might just better both of its big rivals. As we've seen, neither Porsche nor Mercedes is exactly resting on its laurels, so it's been down to BMW to continue developing the Z4 in order to keep up. The flagship sDrive35is variant we're looking at here doesn't get too many changes under the bonnet to its glorious-sounding 340bhp six cylinder engine but then, none were needed. It does however, get a slightly smarter look and continues to offer an much better value option than its nearest Mercedes SLK350 rival.
Are the days of the six-cylinder engine in BMW's Z4 numbered? BMW and six-pot engines have been almost inseparable down the years but with the latest Z4 range, most of the powerplants on offer squirt fuel into a quartet of cylinders, with the sixes being reserved for the range-topping models only. Like the 340bhp sDrive35is we're looking at here. This comes only with M DCT 7-speed twin-clutch auto transmission and makes 62mph from rest in just 4.8s. Unlike the 3 Series Convertible, the first car BMW made with a metal folding roof, this Z4 has managed to retain the German brand's famed 50:50 weight distribution with the roof up but ironically, it's with the roof down and the extra weight over the rear wheels that it feels most responsive. There's virtually no body roll and in the dry at least, you rarely run out of grip. Most owners will appreciate the Adaptive M Sport Suspension which enables you to adjust the dampers depending on the driving conditions. Most of the time, you'll only use two settings - 'Normal' and the stiffer 'Sport' - but there is also a 'Sport+' setting which lowers the car by 10mm, firming things up still further for racetrack use and offering 10% more driver leeway before the stability control cuts in.
Design and Build
Most cars with metal folding roofs look a bit ungainly in their proportions, but the Z4 has a classic roadster profile with long bonnet and a pert glasshouse. 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. The detailing might be neat but so is the packaging. The solid roof made the second generation Z4 185kg heavier than its fabric-topped predecessor and meant a reduction in boot space (to just 180-litres with the roof down). Still, it's no worse than its arch-rival, Mercedes' SLK in this respect and the Z4 has the advantage of being able to boost its 310-litre roof-up capacity via an optional ski-flap in the boot. Thus equipped, you could carry either a couple of sets of shortish skis or, more ambitiously, a couple of sets of golf clubs. Annoyingly, you have to pay over £500 extra for the 'Comfort Access' option which enables you to raise this folded roof sandwich slightly to get hold of bulky stuff you put in the boot when the roof was up but which otherwise becomes trapped there when the roof is down. Many owners will want to avoid this problem by using the 15.5-litre interior storage area behind the seats. Otherwise, irritations are notable by their absence, unless you count the fact that the folding roof, which electro-hydraulically raises or lowers in just 20 seconds, can only be used when stationary.
Market and Model
Expect to pay around £46,000 for this flagship 340bhp sDrive35is Z4, pretty much the same as you'd have to find for the slower Mercedes SLK350. The only other six cylinder Z4 option is the 306bhp sDrive35i which, with 306bhp on tap, costs around £5,000 less (though can be ordered in manual gearbox form). Whichever model you choose, equipment levels offer just about everything you could want, even at this price point. Standard equipment now includes leather upholstery, a DAB radio, Xenon headlights, Bluetooth, USB connectivity and a Sport multi-function steering wheel.. Three additional colours of Mineral Grey, Glacier Silver and Valencia Orange are offered, while two revised styles of alloy wheel (17-inch and an 18-inch V-spoke styling wheels) are available. BMW is also offering the Pure Traction Design package. Available exclusively in Valencia Orange with an optional black contrast roof, this package also comes with Sport seats in Alcantara and leather with contrast stitching, Anthracite headlining and a unique metal weave interior trim. The Pure Traction Design package costs from £550 up to £2,240, depending on the model within the Z4 range it is ordered on.
Cost of Ownership
All of the latest BMW Z4s come as standard with facets of BMW's award-winning EfficientDynamics programme. Technologies that improve engine performance while enhancing economy and cutting emissions include Brake Energy Regeneration, Electric Power Steering with Servotronic, Reduced Rolling Resistance Tyres, on-demand control of the engine's ancillaries and Optimum Shift Indicator on manual transmission cars. The BMW Z4 also adheres to a philosophy of lightweight construction with the front suspension and subframe being largely made from aluminium. This results in excellent fuel economy figures for the sDrive35is that are actually slightly better than those of the lower-powered sDrive35i. So expect 31.4mpg on the combined cycle and 210g/km of CO2. Expect strong residuals in the 35-42% bracket after 3 years or 36,000 miles.
The BMW Z4 has matured extremely well. Whereas some sportscars tend to go to seed the further they get from their initial launch date, others just improve incrementally and the Z4 has done just that. Slowly and methodically, it has developed into an all-rounder that's tough to beat. No, this top sDrive35is isn't as sharp as a Porsche Boxster to drive, but if you're not flogging it round track days, it might well be the better all-round road car. The added refinement, safety and security of that folding hard top roof gives it a real edge. Added equipment, strong build quality and amazing efficiency also counts in its favour. Overall? Well, the Z4 might not be the first car you look at when choosing a sports roadster but look at it you must, especially if you've the £45,000 budget required for this top version. It's now just too good not to.