The 2010 BMW Z4 is offered in two models. The Z4 sDrive30i sports a 255-horsepower, 3.0-liter inline-six; a 300-horsepower, twin-turbo version of that engine comes in the sDrive35i. Cars.com reports 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 pound-feet of torque are appealing on paper, but Edmunds says you really can't go wrong with either of the 2010 BMW Z4's "excellent powertrains." TheCarConnection.com's editors feel the base six has a familiar BMW growl and builds even power up to its 6,000-rpm redline; with a manual shifter, its acceleration and feel are pure classic roadster, not overwhelmingly exotic. The turbo version's more guttural and more of a high-speed hammer, with effortless high-speed passing and strong power for sinewy mountain roads.
Both versions have a standard six-speed manual; Cars.com notes "BMW says the manual shifter has the shortest throws of any stick shift it makes." The base car has an optional automatic with manual shift mode. The 2010 Z4 turbo has an option for BMW's new seven-speed dual-clutch automatic, which includes steering-wheel paddle shifters so that shifts can be ordered up at the tap of a thumb (for downshifts) or fingertips (upshifts). The dual-clutch gearbox lets drivers choose gears and then reverts to an automatic shift mode, or it can be locked in Manual mode for all-paddle control. 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.
The turbo six with the dual-clutch transmission is an exhilarating ride; shifts are quick, smooth, and without a jolt, making it easy to keep the power at a boil. Jalopnik raves that at "any gear, any speed, the new Z4 has huge amounts of shove, culminating in a still impressive top end rush." A 0-60 mph time of 5.0 seconds is possible (the non-turbo six can manage 5.6 seconds). Top speed with a Sport package can hit 150 mph; it's 130 mph without.
Impressive fuel economy comes with any version; the base manual Z4 earns 19/29 mpg fuel economy ratings, and the turbo dual-clutch is rated at 17/24 mpg.
Handling and ride are electronically influenced with the Z4's addition of Driving Dynamics Control. Three modes-Normal, Sport, and Sport+-are programmed into the car's electronic controls for steering feel, automatic-transmission shift speed, and stability control response. In cars equipped with the optional Adaptive M Suspension with Electronic Damping Control (part of the Sport Package), it also controls the suspension damping. With the adaptive suspension, the Z4 is remarkably flexible, soaking up patchy bumps and even coarse, jiggly surfaces but tightening up for the esses and quick maneuvers. 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."
The Z4 grips and induces grins, but the steering does pay a price in feedback: It's a touch too quick, and there's little difference in feel as the Z4 passes over smooth to coarse surfaces. 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." Car and Driver contends "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, the Z4's big, smoothly modulating brakes feel responsive but not touchy, firm but not unyielding. 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."