The BMW nomenclature for the new BMW Z4 roadster may raise a few eyebrows, but few will question the hardtop convertible's capabilities once they spend some time behind the wheel.
The 2009 BMW Z4 is available with a pair of BMW's famous inline-six engines, and TheCarConnection.com's research shows that both are silky smooth. The BMW Z4 2009 lineup is composed of two models—the sDrive30i and sDrive35i—which are distinguished by their engines. Cars.com reports that the "sDrive30i's 3.0-liter six-cylinder engine makes 255 horsepower and 220 pounds-feet of torque," while the sDrive35i gets "a twin-turbo 3.0-liter six-cylinder with 300 hp and 300 pounds-feet of torque." The twin-turbo's extra 45 horses and significant 80 pounds-feet of torque are appealing on paper, but Edmunds says you really can't go wrong with either of the 2009 BMW Z4's "excellent powertrains." Acceleration is quick with either engine, and Autoblog reviewers report that "the automaker is conservatively quoting 5.6 seconds to 60 mph for the sDrive30i manual and 6.0 seconds with the automatic." For those looking to up the power ante, Motor Trend notes that the BMW Z4 sDrive35i "will reportedly hit 60 in 5 sec flat." Just as impressive as the acceleration numbers is the width of the power band; Jalopnik raves that at "any gear, any speed, the new Z4 has huge amounts of shove, culminating in a still impressive top end rush."
For the fully revised BMW Z4 2009 lineup, the German automaker brings its fantastic dual-clutch automatic transmission over from the M line and makes it available on the BMW Z4 sDrive35i. Car and Driver says that this automatic, which offers seven gears, "is the first application of a double-clutch gearbox in a BMW outside of the M3," and they note that "all the gear ratios except for second are the same" between the two vehicles. Drivers still have the option of shifting for themselves, as Motor Trend points out that "a six-speed manual gearbox serves as standard equipment for both the Z4 sDrive30i and sDrive35i," while a six-speed automatic is also available for the sDrive30i. Cars.com reviewers approve of both transmissions and report that "BMW says the manual shifter has the shortest throws of any stick shift it makes," while "both automatics have steering-wheel paddle shifters," which are becoming standard fare on most sports cars (especially at this price point).
One of the major benefits of a powerful six-cylinder under the hood versus a V-8 is the improved fuel economy afforded by having two fewer cylinders. Although the BMW Z4 2009 might not be environmentalists' first choice of automobile, they would undoubtedly prefer it over some of the more exotic—and thirstier—performance cars on the market. According to the official EPA estimates, the BMW Z4 sDrive30i with the manual transmission should return 19 mpg city and 28 mpg highway, while the automatic gets a boost to 29 mpg on the highway. For the turbocharged sDrive35i, the EPA estimates that drivers will get 18 mpg city and 25 mpg highway with the manual, with those numbers dropping to 17/24 mpg for the automatic.
BMW has built an almost unshakable reputation upon the incredible handling dynamics of its vehicles, but some reviewers find fault with the BMW Z4's power steering setup. Edmunds reports that the "electric power steering is uncharacteristically numb for a BMW," while Autoblog similarly deems steering as "uncharacteristically light and numb for a BMW." Fortunately, that's about the only source of criticism that TheCarConnection.com's research uncovers, and in nearly every other handling regard, the 2009 BMW Z4 is every bit a Bavarian superstar. Jalopnik compares the current BMW Z4 to the outgoing Z4 M by commenting that "where the Z4 M was a one-trick pony—great at corners, but harsh everywhere else—the new car is at least as capable without sacrificing a smooth ride." Motor Trend reviewers credit the smooth ride to the optional "Adaptive M Suspension with Electronic Dampening Control," which is reportedly "so fast in changing compression and rebound on the shock absorbers that input, say a pothole, from the front suspension can be processed and adjustments can be made before the rear wheels reach the pothole."
Overall, Car and Driver reports that "the Z4 moves sharply along twisty roads, but the steering feel and the extreme rearward driving position make for a personality that is more deliberate than darty." When it's time to put an end to the fun, Car and Driver says the BMW Z4's brakes are "prone to fade after repeated hard stops, despite relatively large 13.7-inch discs in front and 11.8-inch discs in the rear."