The styling of the BMW 6 Series is an interesting bit of design, with the Coupe and Convertible nearly identical except for their tops.
The twin-kidney grille, quad headlamps and other classic cues readily identify the 6 Series cars as BMWs. The M6 versions get a uniquely styled, more strongly sculpted front fascia. The 6 Series shares some key elements with BMW's 5 Series sedan, but the 6 Series was designed from the ground up as a Coupe, and then as a Convertible, rather than starting with a sedan and eliminating two doors or starting with a coupe and chopping off the top.
This is a classic BMW 6 Series: The front and rear overhangs (the distances from the wheels to the bumpers) are short. The cabin separates the long hood from the short deck. The 6 Series cars are shorter than the 5 Series sedans, but they benefit from a relatively long wheelbase, which contributes to stability and handling.
The turn signals are located above squinty-eyed, compound headlamps, which wrap well around the corners to the sides of the car. The grilles take front and center stage with no bumper ledge in front of them. When viewed from overhead, the front corners look rounded, giving the 6 Series a shark-like nose.
In profile, the lines are sculpted but clean. Sleek, Euro-style combination side lights-cum-turn signals in a thin slit at the trailing edge of the front wheel wells give the impression of attention to detail and on the M models discreetly house the unique, stylized logo that distinguishes those from the 650i models. The 6 Series looks raciest in front three-quarter view, which happens to be our favorite angle on the car.
From the rear the tail lamps and badge label it as a BMW, but the back end looks different from past BMWs. The tail lamps wrap around to the sides, so there's no precise break where the rear of the car ends and the side begins. As with the new 7 Series sedans, some critics don't like the way the rear deck looks somewhat disconnected from and perched atop the rear fenders. BMW points out that the high deck improves downforce, and therefore higher-speed stability, and also allows for a big trunk.
There are also some interesting design features that aren't apparent to the eye, starting with extensive use of weight-saving materials. From the windshield forward, the 6 Series load-bearing structure is made of aluminum, just like a commercial airliner's. Its doors and hood are also aluminum; the front fenders and trunk lid are composite materials. A carbon fiber roof on the M6 Coupe reduces weight without compromising safety. At the same time, because it's the roof that's lighter, the effect is to lower the car's center of gravity. The underbody is shrouded in more high-tech plastic, much like the wind tunnel-groomed bottoms of F1 race cars, to improve aerodynamic efficiency.
The soft top looks great. The rear glass can be raised or lowered like a side window by pressing a button. BMW has reinforced the B-pillars and the lower sides of the car's frame, and built the windshield with an extra-high-strength frame. This not only improves rigidity, but also adds an extra element of safety in the unlikely event of a rollover.
The 6 Series standard adaptive headlamps pivot to aim toward the inside of a corner as the steering wheel is turned. This helps throw light around a bend, reducing shadows and improving visibility for the driver. Sometimes just that extra moment of warning can make for a safer and more enjoyable drive. The 6 Series also features BMW's adaptive LED brake lights, which illuminate more intensely in a panic stop. BMW contends this conveys the gravity of the situation to drivers following when you slam on the brakes, but it presumes those following know enough to understand the brighter brake lights' warning message.
The BMW 6 Series comes with complimentary high-performance driving instruction at the BMW Performance Center in South Carolina, which includes accommodations, gourmet meals, transportation and instruction for the two-day program. We can't think of a better way to get to know these machines. Some reviewers have complained about BMW's high-tech control systems messing up the purity and driving satisfaction that have long characterized the brand, but we have no such gripes with either of the 650i versions, which immediately become an extension of the driver, flawlessly executing his or her wishes. Our take on the M6 is decidedly different.
Put simply, the BMW 650i is smooth and precise. It's easy to drive, always poised, and satisfying to drive at a brisk pace. The ride is taut but not harsh. The brakes take some getting used to but do their job with certainty. The accelerator is easy to modulate, and the steering is sharp. All the important controls work cohesively, making for a smooth driving experience.
The engine is silky smooth and tractable for easy going around town or in stop-and-go traffic. Yet you're rewarded with immediate response whenever you press down on the accelerator. The silky response of the 650i's 32-valve V8 benefits from Valvetronic variable valve timing and variable lift, which allows an impressive combination of low-rev, off-the-line acceleration and free-breathing, high-rev horsepower. The V8's breathing is controlled entirely by the valves. (Technically, there is no throttle, so the go pedal is rightly called an accelerator.) It's a fascinating engine for engineers and car buffs, but what it means for a driver is loads of power throughout the rev range, and the 650i responds immediately in any situation. The engine sounds great, emitting a guttural roar under hard acceleration through its nicely tuned exhaust system. Response is impressive in either the coupe or convertible, though convertible drivers enjoy those sweet engine sounds a little more intimately.
Of the two transmissions available with the 650i, we recommend the six-speed Sport Automatic, unless you're a serious enthusiast, in which case we recommend the six-speed manual.
The automatic is smooth around town and very responsive for spirited driving. In fact, a 650i with the automatic is nearly as quick as a well-driven 650i with the manual. It offers a Sport setting that moves shift points to higher revs and quickens downshifts for increased response. The manual mode allows the driver to shift semi-manually, imparting some of the same involvement as a manual. For everyday driving we prefer to use it in the fully automatic mode.
The six-speed manual gearbox is smooth, precise and easy to shift, with easy clutch pedal effort. It's an excellent choice, unless hours of stop-and-go traffic is part of your daily routine.
The 650i offers a nice balance of ride and handling. Though taut, it doesn't beat up your passenger on rippled highways. The springs and shocks are firmer than those in the standard 5 Series sedans, and the 6 Series cars ride lower. A 650i is absolutely joyful on a winding highway, as we discovered on some mountain roads near Santa Barbara. Handling is precise, with a superb self-centering feel to the steering. The car can be driven very hard into tight corners, and it tracks through high-speed turns like it's on rails. The suspension is tuned to minimize undesirable behavior when braking hard, accelerating hard, or lifting off the gas while cornering. Our car was equipped with Active Steering, which improves high-speed stability while making it easier to steer at slow or parking lot speeds. Some drivers don't like BMW's active steering; we're not among them.
Active Roll Stabilization dramatically reduces body roll (lean) when the 650i corners. As the car leans into a corner, the anti-roll bars are twisted by little hydraulic motors that counteract the body lean, so the 650i leans very little, even in hard cornering. In addition to increasing driver confidence, the system improves handling over bumps, increases cornering capability and improves steering response.
Push the 650i past the limit of the tires and the Dynamic Stability Control and other active safety systems kick in, allowing the car to motor around corners with little drama. The DSC works toward keeping the car from skidding into understeer or oversteer, making it easier for the driver to maintain control. Simply aim the 650i where you want to go and it'll go there, assuming the laws of physics allow it.
The brakes are excellent. The brake discs consist of high-carbon, cast-iron outer portions, or rotors, which constitute the conventional braking surfaces, with aluminum center sections, which mount the rotors to the vehicle. The benefits are less weight and reduced rotor deformation, or warping, under hard braking. The front brake calipers are also aluminum, for further weight savings. These brakes are fully up to the performance of the 6 Series.
Yet, for its impressive performance envelope and response, the 650i is not the least bit balky when driven at a lazy pace, and that's important for a luxury car. The 650i models come standard with aggressive, 245/45VR18, high-performance, run-flat tires. The Coupe and Convertible we drove were equipped with 19-inch wheels, part of the optional Sport Package, and they rode well. The main drawback is more noise over bumps or pavement joints.
The 650i Convertible is remarkably quiet with the top up, nearly as quiet as the Coupe. Wind noise is hardly more noticeable. The power rear windscreen can be lowered even when the top is up, though we didn't find it significantly added to air circulation. Conversely, the rear glass can be raised when the top is down to act as a wind blocker, but turbulence with the top down was minimal in any case, and raising and lowering the glass didn't seem to make a big difference. In short, this is a fun feature, and we like having it, but we could find no significant practical benefit. With the windows up and top down, the 650i convertible makes for great open motoring even on briskly cool days. We prefer to put all the windows down, however, because it looks cooler.
The M6 is everything the 650i is and more. And therein lies the disconnect, the proof that sometimes more can be too much. The ride is stiff, quite noticeably so on bumpy neighborhood streets. Active Steering is not offered, nor is Active Roll Stabilization; perhaps the engineers assumed the more aggressive suspension made it unnecessary. Too bad, as we prefer the elegance of the active setup to the less refined settings of the M6. The short sidewalls on the low-profile tires don't help, magnifying the suspension's limited compliance.
The Sequential Manual Gearbox is especially distasteful, almost overbearing in its insistence on managing every shift, up or down, with its own pre-programmed sequence and pace. In Automatic mode, it shifts up only when it's good and ready; yes, there's a switch at the base of the shift surround that adjusts the timing between shifts, but we never found a setting, among the 11 programs provided (six for the manual function or S-mode, and five for the automatic function, or D-mode), that delivered the quickness, smoothness and precision we achieve using a clutch pedal. It's only marginally better in Manual mode, where you shift by tapping the lever forward for a lower gear or rearward for a higher gear or by working the appropriate lever mounted to the steering wheel. In Manual mode, the driver at least gets to control the timing of the shift. In Auto model it downshifts as the M6 slows to a stop, dutifully double-clutching and blipping the throttle between gears, which sounds neat.
And when that long-awaited opening appears in oncoming traffic on a busy two-lane road, flooring the accelerator does not deliver that vital, immediate kick-down to an appropriate passing gear. Instead, first the transmission's brain has to figure out what gear is appropriate, and then it ponderously double clutches its way to that gear, all while you're anxiously watching that once-beckoning opening rapidly shrinking. This hesitation shows up in other unusual spots, for example, coasting up to a Stop sign at the top of a hill; the SMG pauses as it downshifts to first gear when taking off. This hesitation can be annoying.
At the other end of the spectrum, like in a tight parking space, trying to ease the car ahead or back two or three inches is equally frustrating. When we'd press the accelerator enough to get the clutch to engage, it did so abruptly, making the car lurch forward or backward more than we wanted. Using the brake pedal to minimize the lurch didn't help as that blocked the clutch from engaging. Ultimately, we had to ask the other car's driver, who fortunately was nearby, to move the car so we could escape the parking space. All hope is not lost, however; simply choose the six-speed, manual gearbox.
The M6 engine is a mixed bag. On the downside, a V10 is inherently unbalanced, with crankpins awkwardly dispersed around the crankshaft's center, unlike a 90-degree V8 or a 60-degree V6. For another, that's a lot of moving parts, even more than usual when all the parts necessary to suppress the engine's disharmonies, with gaps and gears and chains spinning, clicking and meshing, all of which has to be somehow muted while left essentially unrestrained. And, quite frankly, to our ears, the M6 comes up short in this effort. We enjoy the musical mechanical sounds a finely tuned engine produces as much as the next person, but those emanating from the M6 were more raw and raucous, almost cheap sounding, than rich and rewarding. This includes the raspy exhaust.
On the upside, however, the engine benefits to a limited degree from BMW's participation in F1 motor racing. Every cylinder has its own throttle butterfly, for example, which is very high tech, and engine lubrication is dry sump, which is more commonly found in race cars. And we confess we did get a kick out of the three, computer-managed power settings, ranging from something you might feel halfway comfortable turning over to a parking valet to one that buries your backside in the M6's admittedly unsoft seats.
Beyond these troubling specifics, the M6, in either coupe or convertible, is comparable to the 650i, as in, reassuringly BMW-like. Again, while we like the ARS and the Active Steering, the ride, although stiff, is well managed, and steering is direct and supremely responsive with reassuring on-center feel.
The BMW 6 Series comes in four forms: The 650i Coupe ($78,450), the 650i Convertible ($85,550), the M6 Coupe ($102,350), and the M6 Convertible ($108,150).
BMW 650i models are powered a 360-hp, 4.8-liter V8 with a choice of two transmissions: A six-speed manual or the six-speed Sport Automatic. The Sport Automatic can be operated in an automatic mode, or shifted with paddles on the steering wheel. The 650i Coupe and Convertible also utilize BMW's E-shift selector, a lever which is tipped in one direction or the other and, for most normal functions, returns to the same starting position. The Sport Automatic is the standard equipment transmission.
M6 models feature a 500-hp, 5.0-liter V10 with the seven-speed Sequential Manual Gearbox or a six-speed manual.
All 6 Series models come loaded with an impressive array of standard features, including leather upholstery; choices of interior trim; dual-zone automatic climate control with air cleaner; a high-power, eight-speaker stereo; xenon adaptive headlamps; moonroof; auto-dim mirrors inside and out; and BMW's Park Distance Control for front and rear.
The long list of available options for 650i models includes the Cold Weather Package ($750), the Sport Package ($3,900), Active Steering ($1,550), radar-managed Active Cruise Control ($2,400), head-up display ($1,200), night vision ($2,200), Premium sound system ($2,000), Satellite radio with one-year trial subscription ($595), and Comfort Access keyless unlock and engine start and stop ($1,000).
Options on the M6 models include the head-up display, Comfort Access, black carbon fiber interior trim ($300) and Merino full leather upholstery ($3,000 on Coupe, $3,300 on Convertible).
The very comprehensive of active and passive safety features include multi-stage front airbags and front seat-mounted side-impact airbags. Coupes are equipped with curtain-style head protection airbags, while Convertibles have automatic rollover protection that deploys high strength roll hoops behind the rear seats. Rear seats have LATCH child safety seat hooks and anchors. Accident avoidance features that come standard include electronic stability control, ABS with brake assist and electronic brake-force distribution. BMW Assist telematics, with automatic collision notification, an SOS button and roadside assistance comes standard. Tire-pressure monitors come standard along with a really cool first-aid kit.