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From its active suspension to its cabin tech, the 2009 BMW 650i Convertible is the quintessential tech car, so we should be in love with this example of German engineering. But two design elements ruin what could be the beginning of a beautiful relationship: the 650i's trunk and iDrive's frustrating interface.
We could overlook these two faults, as the car is so enjoyable to drive thanks to its performance technology. And putting the convertible top down on a sunny day makes it even better, while cabin tech interfaces with cell phones and iPods, and lets us avoid bad traffic. But these positive elements can be found on other BMW models, such as the new 3-series, leaving the 650i as the ugly sibling.
On the road
We can't just jump into a BMW and take off, at least not initially. First, there's cell phone pairing, a task made easy with the car's onscreen instructions. We particularly like that BMW lets us use a custom PIN between car and phone.
Once the phone is set up, then we select our music source. In the 2009 BMW 650i Convertible, that means a choice between satellite radio, CD, or iPod. As we already paired an iPhone to the car's phone system, we might as well plug it into the iPod port and stow it in the center console.
Having the top up or down is another decision to make before driving the 650i Convertible.
And before we roll out of the garage, we have to set the 650i Convertible for the type of driving we will be doing. First of all, what's the weather like? Sunny. So, we put the convertible top down. Now, as we are initially going to be on city streets, we make sure the suspension is in normal mode and the transmission is in Drive.
Yes, there's a lot to do before pushing the gas pedal, but once the car is set up, it exhibits those BMW driving characteristics we know and love. The 650i is a big car with a big engine, but, in classic coupe configuration, the rear seats are virtually useless.
In tight urban conditions, the car is easily maneuverable, with the thick steering wheel providing quick turn response. And even with the transmission in Drive mode, the 4.8-liter engine offers the ready power required to take advantage of traffic openings. Cruising on the freeway, the 650i shows its luxury side. Even with the top down, the ride is nice at 70 mph, and the audio system manages to overcome wind and road noise.
Sport modes for the transmission and suspension are easily set with controls on the console.
When we finally make it to the mountain roads, with all their twists and turns, the 650i shows how easily it handles sport driving. Pushing the Sport button on the console tightens up the suspension, and pushing the shifter over to the Sport/Manual side keeps engine speed high. Although an automatic, this transmission does a good job of seeking the right gear, downshifting when you hit the brakes in preparation for powering through a turn.
And it's this dual character--the capability to go from cruising to hard cornering with minimal fuss--which typifies BMW engineering, and shows itself to a good degree in the 650i Convertible.
In the cabin
We obviously found a lot to like while driving the 2009 BMW 650i Convertible, and some of its cabin tech contributes to the experience. But we can't say that about the iDrive interface, which includes frustrations such as taking four control moves just to get a map displayed. Fortunately, BMW is in the process of radically updating this interface. We got our first taste of the new iDrive in the BMW 335d, and found it a vast improvement.
The navigation system in the 650i Convertible is a mixed bag. Being DVD-based, its response times are slow, which can make entering a street address particularly tedious as you wait for it to update a list of street or city names. But it has some nice features as well, such as live traffic with automatic detouring. It will look along a programmed route and alert you to any traffic slowdowns, and offer to find a detour.
We found that route guidance with this navigation system can be stubborn. We programmed in a destination, but decided we didn't want to take the route it offered. For the next 10 miles it tried to get us to use its original route, suggesting turns at every block. But we persisted, and it finally recalculated for the route we wanted.
The new Lane Departure Warning system works above 40 mph, buzzing the steering wheel as an alert.
This 650i Convertible came with a feature we hadn't seen from BMW before: lane departure warning. A button on the steering wheel lets you turn it on or off, and it shows up in both the instrument cluster and head-up display with a graphic showing lane lines. It only takes effect above 40 mph and will buzz the steering wheel if you cross a lane line without signaling. In practice, it generally worked well, although we did find a stretch where it was oversensitive, continually buzzing the wheel even though the car was in a proper lane. Pavement imperfections confused it.
Our 650i Convertible came with the Premium sound package, bundling a six-disc changer, iPod and USB port, and upgraded audio system. The 11 speakers of this Logic7 system produced above-average sound quality, and the amp, in typical BMW fashion, had plenty of power. The iPod interface suffers a little from the iDrive paradigm, but is generally workable.
We mentioned above how easy it is to pair a phone to this system. One particular feature we like about this phone support is that you can see your phone's contact list on the car's LCD, and choose people to call from there.
Under the hood
BMW's best tech comes in the power train and suspension. The engine is a 4.8-liter V-8 producing 360 horsepower and 360 pound-feet of torque. That those two numbers are equal is probably intentional on the part of BMW engineers. The engine benefits from BMW's unique throttle system, which uses valve lift to regulate engine speed rather than a conventional gas flow control.
The 4.8-liter V-8 produces 360 horsepower and 360 pound-feet of torque, moving the car easily.
That engine tuning moves the 650i Convertible from 0 to 60 mph in 5.7 seconds. Fuel economy is rated at 15 mpg city and 23 mpg highway. In our hands, the 650i turned in a very reasonable 19.4 mpg. We've seen similar fuel economy in many V-6 sedans and coupes.
The engine is attached to a six-speed automatic, with Sport mode and paddle shifters for its manual mode. A six-speed manual transmission is also available. We're not crazy about the push-and-pull paddle shifters used by BMW; they look more cosmetic than useful.
Cornering is aided by BMW's Active Roll Stabilization technology, which uses hydraulic antiroll bars to counter body roll in turns more effectively than fixed antiroll bars can. In our experience, this system works seamlessly, keeping the car very flat in corners while allowing a more comfortable drive on the freeway.
The 2009 BMW 650i Convertible comes in at a base price of $84,900. The main tech options in our car were the Premium sound package for $2,000 (essential because of the iPod support), the new Lane Departure Warning for $500, and the head-up display for $1,200. Navigation and Bluetooth phone support are included in the base price. Other options and the destination charge brought the total for our car up to $94,070. Although a high price, the 650i Convertible has more advanced performance technology than the $200,000 Aston Martin DB9 Volante (still, the DB9 is a much better looking car).
In our ratings, we give the 650i Convertible top marks for performance technology. BMW engineering always impresses. Cabin tech gets downgraded a bit for the outdated navigation system. A hard drive-based nav system is part of BMW's upcoming cabin tech update. The 650i Convertible suffers the most in our design rating, both for the poor iDrive interface and the abysmal trunk lid.