The current E89 BMW Z4 won’t spawn an M version. For some that will be a disappointment, but the rest of us are rejoicing because instead BMW’s M Division is readying a sub-M3, the 1-series M Coupe.
That means the hottest Z4 is this, the sDrive 35iS, whose engine will power the 1-serie M Coupe, but actually costs £5290 more at £45,280. How good is it? Read on for CAR’s first drive review of the new BMW sDrive 35iS.
How does a BMW Z4 sDrive 35i become a BMW Z4 sDrive 35iS?
Let’s start with the engine, which is a twin-turbo, direct injection 3.0-litre straight six. Power goes up from the 302bhp at 5800rpm to 335bhp at 5900rpm, but the blowers mean it’s a torquey engine too: 295lb ft becomes 332lb ft, with another 37lb ft available via an overboost facility. And you still get the same 31.4mpg and 210g/km as the less powerful 35i.
The 35iS engine is the same engine that will power the forthcoming 1-series M Coupe, and with special acoustic flaps in the exhaust and a modified silencer this Z4 sounds rorty and rough and aggressive. The mid-range oomph lets you know it’s turbocharged, but its willingness to rev, great exhaust note and decent throttle response will make you think otherwise. It’s a cracking engine, with the character that’s usually so sorely missing from forced-induction units, and the standard-fit dual-clutch ‘box sends some nice little booms down the twin pipes on upshifts.
What’s the BMW Z4 sDrive 35iS like on the road?
Quick, very quick. Paper figures proclaim 0-62mph in 4.8 seconds, three-tenths quicker than a DCT-equipped 35i, while all that torque from the creamy engine means easy overtaking. M3 owners will have to wring their V8’s out to 8300rpm (no bad thing) to keep ahead.
Speaking of M3’s, while the M-DCT transmission in our long-term Competition Pack car is super-sharp, most of the CAR office initially mistook the gearbox in the Z4 35iS for a torque converter. The changes aren’t snapped through, but slurred, and the paddles aren’t simple right-up/left-down, but BMW’s confusing push/pull combo on both sides. You might think the more relaxed shifts might suit the Z4, but there’s nothing wrong with the refinement of the changes in an M3 when the M-DCT isn’t set to full-ferocity mode.
What about the rest of the iS-specific upgrades?
Every Z4 already features BMW’s Drive Dynamic Control system, which allows you to select Normal, Sport and Sport+ modes and thus adjust the throttle, steering and DSC, and on dual-clutch cars – like the 35iS – the shift speed times and shift points. Whatever setting you select the revised-for-the-35iS steering is quick (though the electric set-up lacks feel) and the rest of the car can’t quite keep up. Steering and suspension always feel a bit out of sync, and the Z4 never quite gels with a good British B-road. It’s a hard car to drive quickly and smoothly, and is much better suited to fast cruising.
The more aggressive bodykit means the 35iS is a few millimetres longer, the 10mm suspension drop means it sits a little lower, and the bumpers, sills, big wheels and fat exhausts help transform the svelte roadster into a butch-looking drop-top. There’s no brake upgrade, so the 35iS sticks with the 35i’s 348mm front and 324mm rear discs, but the alloys are an inch bigger and the tyres are now 225/40 (front) and 255/35 (rear), from 225/45s and 255/40s.
Despite all the tweaks, BMW claims the 35iS is no heavier than a 35i; 1600kg doesn’t make it a lightweight, but then this Z4 does have a trick two-piece metal roof that can be raised or lowered in just 20 seconds.
As good as ever. The old Z4 had a fairly shonky interior, but the current car took things a few generations forward when it was released in 2009. It’s more driver-focused than the SLK or Boxster – though can’t match the Porsche’s driving position – and iS upgrades includes sports seats, aluminium carbon-look trim (that’s not a patch on the M3’s carbon-effect leather), and an M Sport steering wheel with those shift paddles.
Don’t come to the Z4 expecting a Boxster-beater and you won’t be disappointed. BMW purposely moved away from the Porsche to create an SLK rival with the current Z4 range, and it’s a role that it better fulfils. Whether it needs such a sporty model is another question, and one answered by the fact that the sum of its parts don’t quite gel. It’s good but not great.
However, just as the not-quite-there TT RS features a cracking, characterful turbo’d five pot that makes it into an exciting car, the Z4 35iS also has an awesome engine that will make you forgive its other foibles. You won’t excuse its shortcomings completely, but it will make you excited at the prospect of the 1-series M Coupe. Wait for that car if you want a sports car, or buy a 3-series drop-top or lesser Z4 if you want a decent convertible.
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