Ed Hellwig, Executive Editor
It's been a long time since BMW had a coupe, let alone a convertible, that could be rightfully called aspirational. Since the demise of the original 6 Series in 1989 and the short-lived run of the 8 Series that ended in 1997, there's been a noticeable void at the top of the BMW lineup. While cars like the Mercedes-Benz SL and Jaguar XK reigned supreme in the high-end convertible market, BMW had only its entry-level 3 Series cabrio to offer in response. BMW never gave any reason for the absence of a flagship two-door, but as North American CEO Tom Purves succinctly put it, "We might have simply lost our way for a time."
With the introduction of the 2004 645Ci convertible, BMW has found its bearings and is firmly back on the path to preeminence. With its sultry lines, sports car performance and uniquely configured soft top, the 645Ci looks as though it was designed with enough personality to make up for all that lost time. It's a grand touring car in the most traditional sense, but there's nothing traditional in the way it goes about delivering on that promise.
Although the 645Ci is more than just a two-door version of the 7 Series sedan, it does share a few of the controversial design elements that debuted on the flagship sedan. From the hooded headlights up front to the awkwardly protruding rear end, the 645Ci has BMW's new design language written all over it. Thankfully, that language has been toned down into a more palatable form that most agree makes for a handsome convertible.
Along with the unmistakable styling cues, the 6 Series borrows several of its sibling's most desirable pieces of hardware. The one and only engine is BMW's ultrasophisticated 4.4-liter V8 that's able to adjust its valves, camshafts and intake manifold to deliver up to 325 horsepower. It does so with typical German precision, yet with the top down and the pedal flat to the floor, the V8 emits a satisfying rumble that reminds you that the Germans still know there's more to the magic of a V8 than just power.
If the sound isn't enough to convince you that the 645Ci possesses more soul than your average luxury convertible, consider the fact that its standard transmission is a six-speed manual. So equipped, the 645Ci is able to sprint to 60 mph is just 5.5 seconds and reach a top speed of 155 mph according to BMW. Buyers seeking a less traditional setup can opt for a six-speed sequential manual gearbox (SMG) that provides the flexibility of a manual with the convenience of an automatic. And if that's not to your liking, there's also a six-speed automatic available that does all the shifting for you.
For those willing to put in the effort, the six-speed manual is still the best route to high-speed satisfaction. There's no substitute for working the gears yourself and BMW's manual gearboxes rarely leave you wishing for more. Going with the SMG option won't cost you much in terms of performance, but the clunky shifts and odd-looking steering wheel paddles are more of an annoying distraction than a usable advantage over the traditional stick. If you really don't want to shift, order up the six-speed automatic and forget about it.
Regardless of which transmission you choose, the 645Ci delivers a level of performance that will satisfy both enthusiasts and boulevard cruisers alike. Drive it hard and the car feels more nimble than its size would suggest (it's as long and wide as a 5 Series sedan). It has all the straight-line stability you would expect in a touring car, but when the road turns twisty it feels equally adept at throwing its weight around. Part of the credit goes to BMW's Active Roll Stabilization (ARS) and Active Steering (AS) systems that provide varying levels of body sway and steering response. Engage "sport" mode and both systems dial up heightened levels of performance that turn the 645Ci into a car with more potential than most owners could ever hope to use.
As adept as the 6 Series is at fulfilling BMW's promise of legendary performance, it's never at a loss when it comes to covering long stretches of highway in perfect comfort, either. The same suspension that's so predictable and planted in corners remains compliant and comfortable over just about any road surface. Models equipped with the larger 19-inch sport package tires and wheels emit a bit more road rumble than you might expect, but even that's not enough to infringe upon the otherwise serene interior.
Wind noise from the soft-top roof is negligible, and even when the top is down, the draft through the cabin is minimal. Going from top up to top down takes just 25 seconds and the process can be initiated while moving at speeds below 20 mph. The design of the top is unique not only for its rear fins, which give it a coupelike profile, but also for the rear window that can be raised or lowered independent of the rest of the roof. As such, the rear window can be lowered when the top is up for more air in the cabin or raised when the top is down to act as a windscreen.
Other than the door panels, the interior of the 6 Series is nearly identical to the latest 5 Series sedan. There are traditional analog gauges, a few choice climate control dials and an iDrive control knob in the center console. Both wood and metallic trim are offered along with three shades of leather beige, black and red. Additional options include a head-up display that projects information onto the windshield, an 11-speaker audio system and active cruise control that automatically maintains a preset distance from the car in front of you.
Passenger space in front is more than adequate, and the multifunction seats provide the kind of support that makes you feel like you could drive all day without ever feeling the need to stretch. Crank up the seat heaters with the windows rolled up and you could drive with the top down in less than perfect conditions in complete comfort. There are rear seats, but the lack of rear legroom makes them more useful as secondary storage than a place to put your friends.
If BMW really was lost for a time, there's no better indication that it's back on track than the 645Ci convertible. Well proportioned on the outside, exquisitely detailed on the inside and a genuine thrill to drive in just about any condition imaginable, there are few convertibles that can match the 6 Series when it comes to delivering a complete package. Its styling may breed a few complaints, but the way it drives will make believers out of anybody.
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