The 2007 BMW M6 Convertible is virtually the same car as the M6 coupe sans haut: same "Power" button that summons an extra 100 horsepower; same three-position damper control button; same seven-speed automated-clutch manual transmission (sadly); same variable differential lock and programmable "M" button that accesses your favorite performance settings (of the 279 possible), or as we prefer, the full-commando max-mental mode the car is capable of.
Although some will consider it sacrilegious to eliminate the beautiful carbon-fiber cover that tops the M6 coupe, the benefit is sheer aural pleasure. With nothing between you and the harmonious bellow of one of the most remarkable engines in production car history, the only thing left to do is slather on some SPF 50 to keep your dermatologist happy and let the sun, wind and sound prickle your senses.
10 little engines
Since it was introduced in the 2006 M5 super sedan, the BMW 5.0-liter V10 (S85B50) has won numerous international awards, to which they may now add the "Engine Note Most Improved by Including a One-Touch Soft-Top Convertible" award. We love the poetic logic and resonance of 10 half-liter 50-horsepower engines working in unison to produce a Dodge Viper-or Corvette Z06-threatening 500 horses (with 3.3 and 2.0 liters smaller displacement, by the way) and 384 pound-feet of torque. It also redlines at a crank-twisting 8250 rpm.
Fundamentally, the BMW V10 comprises 10 engines. It features 10 individual intake trumpets, 10 throttles, 10 cylinders, 10 coils/spark plugs, 10 knock sensors and 10 individual exhaust headers. It's a modern marvel of mechanical skill and computing power originally meant to be a tribute to the BMW F1 engine made obsolete by the FIA's 2006-season rule book. It's the kind of power unit BMW can hang its hat on, even if it's a bit of a "because-we-can" statement. Whatever. We were happy to guzzle down $4.50/gallon of European fuel to probe the edges of the rear-wheel-drive M6 convertible's comfort and speed zones.
"Nice" neighborhood — if you can afford it
BMW chose to introduce the M6 convertible in the elite neighborhood of international shipping magnates and Formula 1 drivers, why? Because the exclusive M6 convertible fits in perfectly with the Ferraris, Lamborghinis and Aston Martins we saw in and around Nice, France. In fact, as we were leaving town for the hills to the north, a tawny, well-groomed man in his F430 Spider nearly rear-ended the car in front of him when he caught sight of our Alpine White drop top.
Base-priced at $108,795 (including $3,700 gas-guzzler tax and $695 destination fee), the M6 convertible is a distinctive car for a discriminating and well-financed buyer. Made in limited numbers, it'll be a rare sight you'll first hear — then see. Our test car was further optioned with keyless entry/starting ($1,000), head-up display ($1,000) and Indianapolis Red Merino leather ($3,500) for a total of $114,295. Yeow.
Finally reaching the hills to the north, with their twisting two-lane roads clinging to the cliffs, we could finally get out in front of the ever present diesel-driving public. Once released, the M6 convertible drives much like the M6 coupe despite the almost 500-pound weight gain.
Part of that load increase is due to the thorough structural reinforcements made in the name of platform integrity. The other part is due to the replacement of an exceptionally light carbon-fiber roof with a folding soft top and all its actuators. Still, when you've got 500 horses to pull your carriage around, they barely notice. In fact, BMW's quote of 4.8 seconds to run from zero to 62 mph (100 kph) is nearly identical to the M6 coupe we recently tested.
Initial turn-in is a little subdued from what we recall in the coupe, but there's no mechanical difference to the Servotronic steering. The suspension tuning is unique to the needs of the convertible, and we still appreciate the three-mode EDC (electronic damper control) dampers. They smoothed out the rough pavement when we wanted to and there was virtually no cowl shake or shudder in the chassis, even in the firmest position.
Here's a trick of the trade: Wedge your pinkie finger in the gap between the back of the door and the interior when traversing some bumpy surfaces to see if you can feel flex. In the M6 convertible, there was very little wiggle or pinch. Well done. The brakes are as phenomenal as we expected, and easily haul down the 4400-pound car. No doubt the monster tires (255/40ZR19 front; 285/35ZR19 rear) help all these gripping characteristics.
In terms of limit handling, we drove to the limits of the narrow mountain roads and never found the limit of the car itself. Even with the weight gain, the engineers found the structural reinforcements actually lowered the car's center of gravity, compared to that of the coupe. Our impression is that there's plenty more capability than roads can handle in most environs, including this one. We'll have to wait for a proper test to see if the convertible can match the coupe's 0.89g skid pad and 67.1-mph slalom performance.
We can't tell you how many times we've had discussions with (beholden) BMW engineers who insist that the car's seven-speed sequential manual gearbox (SMG) is superior to all others of its ilk, and even better than the best test driver's abilities. C'mon.
The truth is that the six-position programmable transmission is the one thing that detracts from the car's otherwise faultless behavior. Three of the six positions are virtually useless (unless you're stuck in a snowbank, and who'd really drive this car in the winter?), and the supposed intelligent software always seems to be in learning mode, never quite anticipating how smoothly or quickly you'd really like the car to shift. Don't even bother with the simulated "Drive" mode. Stick with either position five or six, click the paddles and modulate the throttle for smooth, quick shifts.
For these reasons and the unrelenting U.S. automotive press saying how much we'd prefer a true manual transmission with a third pedal, BMW has conceded it will produce first the M5 sedan (available as soon as the container ships arrive), then M6 coupe (mid-2007), and finally M6 convertible with a D.I.Y. six-speed.
Friends and relatives
It's hard to put a value on a car like this. It offers so much to the so few who can afford it. In terms of relative size, price and performance, there really is no competitor. Name another 2+2 convertible with its capabilities. Some may say the four-seater Bentley Continental GTC, but it costs a bunch more.
The Mercedes-Benz SL55 AMG? Similar power and price, but no backseat at all. Jaguar XKR convertible? Close, but not the performer the M6 is. Even compared to the discontinued BMW Z8 with its mere 400-hp V8, all-aluminum construction and original $128,000 MSRP, the M6 convertible is a deal. That kind of leaves the BMW to stand alone in a class of one. And like we said, it's a nice neighborhood if you can afford it, and the songs the M6 convertible sings nearly justify the six-digit tariff.
Edmunds attended a manufacturer-sponsored event, to which selected members of the press were invited, to facilitate this report.