After the less-than-smooth performance in the city, we were eager to see how the Z4 sDrive35i handled out where the wild things are. But first, we put on some driving music to check the stereo. As we would expect in a fully optioned up BMW, the Z4 sDrive35i didn't lack for audio sources. A port in the console was ready for an iPod or USB drive, the in-dash hard drive has room for MP3s, there's an in-dash single CD player, and the radio plays HD and satellite. Opting for the iPod, iDrive let us select music by artists, album, and genre, although its interface is a bit bizarre, requiring slightly more work with the iDrive controller than should really be necessary.
Those audio sources are played through an optional premium audio system in our Z4 sDrive35i, which uses an amazing 14 speakers complemented by two subwoofers. Did we mention this is a complicated car? Those speakers are powered by a 650-watt amp, and, as part of this optional system, you also get seven-band equalizer on the LCD, with which you can really fine-tune the sound. We took the easier route, adjusting the treble, bass, and mid controls, and the system produced excellent audio. The instrumental reproduction came through with clarity and fine separation, letting us hear snaps from snare drums, twangs from guitar strings, and background sounds that often get lost in multilayered recordings.
We found it very convenient to use an iPhone with this car, plugging it into the iPod port and pairing it up with the Bluetooth phone system. We've been pretty happy with BMW's phone systems for some time, as the company early on had the technology to transfer a phone's contact list to the car, making it available on the LCD. The system in the Z4 sDrive35i provides that same functionality, and it's only eclipsed by the Ford Sync and Kia's new system, both of which let you dial by speaking the name of a contact rather than having to look it up on a screen.
With the navigation system showing us where to go, and loud music blaring from the speakers, it was time to get the Z4 sDrive35i into the fun stuff. We suspected that, with plenty of room to run, any unevenness in throttle modulation would disappear, and the car satisfied us in that regard. Powering around on the freeway, the Z4 sDrive35i proved exceptionally maneuverable, small and nimble enough to take advantage of openings in traffic, and powerful enough to pass just about any other car. The only thing to watch out for was getting too far over the speed limit.
The fun stuff
Taking the Z4 sDrive35i onto one of our favorite routes in Northern California, a good run of twisty roads without a car or house in sight, we found out how well the Sport mode on the transmission works. Through the first set of twists, the Z4 sDrive35i was in its natural element, easily negotiating these corners at speed, immersing us in sublime BMW handling. With the suspension in Sport mode, the car showed tremendous poise, with a willingness to be thrown around.
Letting the transmission's Sport mode pick the gears showed the near-miraculous nature of the DCT. On the straights, it jumped to an appropriate high gear, fourth or fifth, but not too high to get out of the power band. Braking before a corner made the DCT quickly downshift, so that when we were ready to get on the gas again, the car was in second or third, offering plenty of power to shoot into the next straight.
Depending on the speed we entered the corner, the rear of the Z4 sDrive35i would come out in a predictable and controllable manner, letting us keep the nose pointed exactly where we wanted it. Putting it in Sport Plus mode, we found that the car loosens up the traction control substantially, but doesn't turn it all the way off. In this mode, we felt the rear end start to slide out pretty far in the corners, but then the traction control came on to reel the car back in.
Although the gearbox is filled with technical wizardry, manual shifting resulted in quick, tight gear changes. It would take racing driver reflexes to make shifts even close to this quickly. The DCT also accomplishes these shifts smoothly in automatic mode, matching the gear to the revs to keep the car from bucking.
The engine's 306 horsepower is enough to make the Z4 sDrive35i a powerful sports car. BMW claims 5.1 seconds to 62 mph with the seven-speed DCT, and 5.2 seconds to 62 mph with the six-speed manual. We didn't perform any timed runs, but on our various fast starts, the Z4 sDrive35i shot forward, making a satisfying exhaust blast with each gear change.
The DCT also helps the Z4 sDrive35i turn in decent fuel economy. Although hours of hard driving in the hills resulted in only 18.5 mpg, our overall average was 21 mpg, which isn't bad considering the big engine in this car. The EPA rates the Z4 sDrive35i at 18 mpg city and 25 mpg highway.
The 2010 BMW Z4 sDrive35i proved to be a spectacular tech car, from its performance gear through its cabin tech. The twin turbo engine and twin clutch transmission deliver a spectacular driving experience, helped by the adjustable suspension. The cabin tech also offers a lot of practicality, with traffic avoidance integrated with the navigation system, along with full-featured Bluetooth phone and iPod integration. The audio system also delivered excellent sound. The only thing really lacking are other useful information feeds, such as weather, and driver aid technologies, such as blind spot warning. As for design, the Z4 sDrive35i is a good-looking car, but, although iDrive is substantially improved from its previous incarnation, it's still less than perfect.
|Model||2010 BMW Z4|
|Powertrain||Twin-turbo 3-liter inline six cylinder engine|
|EPA fuel economy||18 mpg city/25 mpg highway|
|Observed fuel economy||21 mpg|
|Navigation||Optional hard drive-based, with traffic|
|Bluetooth phone support||Optional|
|Disc player||Single CD, MP3 compatible|
|MP3 player support||iPod integration|
|Other digital audio||HD radio, Satellite radio, USB drive, auxiliary input|
|Audio system||Optional 16 speaker, 650 watts|
|Price as tested||$66,195|