The sports car is not really BMW's thing. The company has tried to make one plenty of times, yet every attempt is greeted by widespread wailing and gnashing of teeth, as if it were somehow shameful that a company that has achieved such excellence in sport sedans should design two-door cars that drive like sport sedans.
Nevertheless, BMW has stepped up once again with another sports car, the 2011 BMW Z4 sDrive35is. We will see if the whingers (mostly British) complain yet again that a BMW doesn't feel like a Porsche, while offering no sound reason why it should.
It was a great relief to most of us when the introduction of the second-generation Z4 revealed a newly mature nature within this package that no longer tried to bludgeon you into submission with pretentions to sportiness. With the 255-horsepower Z4 sDrive30i and 300-hp Z4 sDrive35i, the Z4 seemed to have finally reached equilibrium as a hardtop convertible, more like an Audi TT or Mercedes-Benz SLK than a Porsche Boxster or Cayman.
And yet there were those who were scandalized that the car has become a hardtop convertible and they were shocked that no longer would there be high-performance M versions of the Z4. But in a move that signals BMW has not given up on attempting to entice the enthusiast driver with its latest two-seater, there is now a third Z4, the 2011 BMW Z4 sDrive35is.
Let's Get Serious
The 2010 BMW Z4 sDrive35is wants to take its place next to the Audi TT-RS, Mercedes-Benz SLK and Porsche Boxster S/Cayman S, and it has some visual snap to show it. The style embellishments include a deeper front bumper with a matte-aluminum trim bar in each of the outboard air intakes, more pronounced rocker sills and a rear aero diffuser.
More important, the 35is also gets a reworked suspension with stiffer springs and dampers, a ride height that's lower by 0.4 inch and a set of 18-inch cast-aluminum wheels.
When it goes on sale in North America next month, the Z4 sDrive35is will go head to head with some formidable competition, but it is well up to the job. In fact, we wouldn't be surprised to see this car trump them all.
Performance certainly isn't a problem. The 2011 BMW Z4 sDrive35is's engine is easily the most effective inline-6 with a BMW badge right now, the twin-turbocharged 3.0-liter N54, recently superseded in the cooking 3 Series by the N55 edition with a single twin-scroll turbo. Thanks to a new set of electronics, the output of the Z4 sDrive35is's N54 has increased by 35 hp over the Z4 sDrive35i to 335 hp at 5,900 rpm. Torque also increases by 32 pound-feet to 332 lb-ft at just 1,500 rpm. Thanks to an overboost control, you can actually liberate a further 37 lb-ft of torque, so there's a heady 369 lb-ft at your command for short bursts of full-throttle action.
Command and Control
As impressive as these figures are, they fail to convey the whole story. What the Z4 sDrive35is offers is terrifically strong, infinitely usable and ultimately stirring performance. The delivery is extraordinarily flexible and linear all the way up into the upper reaches of the rev range. This car might not wear an M car's badge, but it certainly feels like one. And the hard-edged exhaust note that rises in intensity until you find the ignition cutout at 6,800 rpm makes it sound for all the world like one, too!
Sending drive to the rear wheels is a seven-speed dual-clutch automated manual transmission, the same Getrag-engineered unit offered as optional equipment for the M3. It is spectacularly good, providing rapid and seamless shifts that fully justify BMW's decision not to even offer the Z4 sDrive35is with a traditional six-speed manual gearbox as on the Z4 sDrive30i and Z4 sDrive35i.
Clearly, a lot of work has gone into perfecting the new dual-clutch unit. You'll notice this in its ability to cope with changes in gear at high engine loads without any discernible pause on the upshifts, and its ability to introduce a hearty blip of the throttle during downshifts to avoid unsettling the chassis when you're braking hard into tight corners. It is just a pity that the tools provided to operate it are so intrinsically flawed, as both the shift buttons on the steering wheel and the traditional gearlever on the center console leave a lot to be desired. (Note to BMW: Two simple shift paddles like those used on the M3 will suffice nicely, thank you very much.)
Nevertheless, the gearing is superbly matched to the eager personality of the engine, providing heady levels of off-the-line acceleration and storming in-gear performance. Officially the Z4 sDrive35is will hit 60 mph from a standstill in 4.7 seconds, some 0.5 second faster than Porsche claims for the Boxster S, no less. More than this, it is the way the new BMW Z4 gathers speed though the gears that really grabs your attention. No matter what the revs or the gear, it's always willing. And with an ability to hit 155 mph before the onset of an electronic limiter, this car is up there with the most potent BMW models on top speed.
Keeping It Together
Yet there's much more to the 2011 BMW Z4 sDrive35is than just a tuned engine. Its steering, body control, grip and overall responses are in an altogether different league from those of the Z4 sDrive35i — so much so that you're left wondering if the two really share the same origins.
The Z4's standard electric-assist steering has been tweaked to endow the sDrive35is with a meatier feel and added levels of feedback compared to lesser versions of the two-seat roadster. It weights up nicely through corners and delivers sharp response both at lower speeds around town and as the pace increases out on the open road.
BMW has also completely revised the kinematic properties of the Z4's aluminum-intensive suspension to provide the sDrive35is with the sort of sharpness that keen drivers will appreciate, together with impressive levels of compliance that everyone appreciates. The MacPherson struts up front and multilinks at the rear have been enhanced by stiffer stabilizer bars at each end, along with firmer springs and recalibrated dampers.
The great thing about the changes BMW has brought to the chassis is that once you get in the zone and start pushing up to the absolute limit, the car doesn't prematurely back away from the action with early stability control intervention — not in dry conditions, at least. The Z4 sDrive35is simply gets on with the job, digging deeper without displaying any worrying tendencies that might force you to back away from the throttle. Even at seriously high cornering speeds, it's extraordinarily eager and imparts a feeling of utter competency.
It's entertaining, too. Pressing the button next to the gearlever to call up the Sport + mode effectively disengages the traction control system, providing the scope for some lurid oversteer for those willing to seek it out.
But the truly admirable achievement is that BMW's suspension engineers have managed to endow the Z4 sDrive35is with such crisp and engaging handling without significantly ruining the ride. Yes, it is firmer and less forgiving of small ruts than the Z4 sDrive35i, but the 35is retains reasonable levels of compliance even in the most extreme Sport + setting for the electrically controlled dampers.
Inside the cabin, the 2011 BMW Z4 sDrive35is scores on the proper sporting feel it imparts. The fabulously supportive, electric-adjustable seats can be set low to the floor, providing a traditional sports-car-style, legs-out-in-front driving position together with an alluring view over the long, contoured hood. The multifunction steering wheel is also nicely proportioned and generously adjustable for both height and reach, making it easy to find just the right balance despite the snug confines of the two-seat cabin.
In front of the driver are gray-face instruments from the M division, just one of a number of touches from BMW's fast-car department. Look elsewhere and you'll also find that the door sills, gearlever, floor mats and even the driver's footrest all carry the evocative M logo. Of course, all of this makes you wonder why BMW didn't just give the Z4 sDrive35is an M badge in the first place, since it looks and feels like one in every respect.
The 2011 BMW Z4 sDrive35is might not be a successor to the M Roadster in name. But in terms of styling, performance, overall dynamic ability and, most important, intrinsic character, it is more than a worthy replacement for BMW's former signature for hard-core drivers (Dr. Burkhardt Goetschel, BMW's former director of research and development and a member of the Formula 1 manufacturer's council, was one).
It's no bargain, though. With a base price of $61,925, this car will set you back almost $10,000 more than the full-fledged M version of the Z4 coupe that was introduced in 2006 and a similar amount over the price of the 2011 BMW Z4 sDrive35i. This car is good, but at such a price, it's clearly going to be relying on dedicated enthusiasts to make it a sales success.
Edmunds attended a manufacturer-sponsored press event to facilitate this report.