There was a moment during my recent time behind the wheel of the M6 that it struck me. I had just enjoyed some opposite lock acrobatics on a twisting mountain road and was turning off it heading to a rather mundane highway. As I did I switched off the hardcore M programming and set the car to comfort. The moment was nothing short of a revelation as the savage beast I was just piloting became the mildest of GT cars.
The M6 unsurprisingly blew me away in almost every performance category. But what completely oblierated my expectations was how comfortable it felt doing not much of anything. Unlike the previous M6 with it ‘s unruly SMG and torque-less V10, the new M6 is perhaps the best ever at being both an M car and simply a car.
There are reasons for this. The biggest lies under the hood with the S63Tü V8. We ‘ve reviewed this engine before in the M5 and the engine it ‘s based on (the S63) in the X5 and X6 M twins. But let ‘s look at some figures to better understand how the complexity of this powerplant creates simplicity on the road.
The all aluminum 4.4L twin scroll twin turbo engine has a 10.0:1 compression ratio to start with. But BMW M wanted a faster revving and more responsive engine while maintaining the incredible drivability of the S63. So they doubled the size of the intercoolers and added valvetronic. This effectively gives the S63Tü 16 intake throttles.
However, instead of upping the power, M went the route of increasing effeciency by 30%. That coupled with the increased capacity of the now metal fuel tank has increased range by 36%.
The result is a car whose personality is split in ways M cars rarely are. Within moments of acceleration with neck snapping downshifts the M6 can be transformed into a docil commuter car that eeks out respectable highway MPG. Drivability is also increased due to maximum torque available at 1,500 rpm (the engine redlines at just over 7,000).
It neither revs like the previous M6 ‘s V10 or sounds nearly as exotic. But it does sound impressive in a high-tech and brutal way. And it can still out-rev your mental capacity to pull the right shift paddle quick enough. The uninitiated will bounce the needle off of the 7,200 rpm redline more than once.
And where the V10 felt like a tamed motorsport product the new twin turbo V8 feels nothing short of otherwordly. There ‘s complexity in its note that almost seems at odds with seamless power delivery.
The complexity in sound comes (unsurprsignly) from the complexity of the mechanicals;
- Twin-scroll turbochargers with zero interference between gas pulses.
- Cross-bank Exhaust Manifold.
- Routing with perfect sequencing of exhaust gas pulses which results in perfectly “regular” charging of each turbine wheel and minimum possible turbo-lag, razor-sharp response, and vastly-improved efficiency.
The S63Tü engine dominates this car even more so than the M5 due to the lack of a top. You hear every aspect of its mechanicals and feel every ounce of it ‘s output.
Engine aside, there ‘s another key contributor to the M6 convertile character; weight. This is the first M car to achieve the dubious honor of weighing more than 4,500lbs. At a stout 4,508 lbs the new M6 Convertible is not sports car. It does not shrink around you like the M5 or likely how the M6 coupe will. It feels big. You never forget that it ‘s 193 inches in length and 75 ” wide.
BMW has succeeded in increasing power, torque, effeciency and drivability. But how does it feel? If you ‘ve read our previous reviews of the new 6 Series line you probably have a good hunch of how we ‘ll feel about the new M6. In short it ‘s a noticable and at times dramatic improvement in almost every way.
Putting this power down to the pavement is BMW M ‘s latest trick rear diff. It ‘s more than just a high torque version of the acclaimed M3 differential though. The control unit is connection with the DSC via a FlexRay high-speed data transfer that constantly cross-checks th data collected by all the various sensors. It then applies the appropriate locking force required to deliver optimum traction and stapbility. The data recorded is also passed on if the stability control system is in MDM mode or even switched off. In total the locking force can be varied continously between 0-100%.
The system also takes into consideration the position of the accelerator pedal, rotational speed of the wheels and the vehicle yaw rate. In short, every potential variable is analyzed and maximum traction is applied in the best possible way in a fraction of a second.
Handling is also sharper and more accurate than the previous generation 6. BMW M took the rather surprising step of bolting the rear subframe directly to the chassis in a bid to improve dynamics. The result is a 4500 lbs car that seems to defy logic with it ‘s ability to feel quick whitted and more eager in the corners than you would think possible. The M5 introduced this last year as the first non limited edition M car with this method of construction, the M6 convertible being the first to land in the US (the M3 GTS and CRT being the first two).
Beyond the rear sub-frame BMW M has also gone to great lengths to make the M6 different and more robust than the standard 6 Series. Driving the 6 Series GC back to back with the M6 made this point obvious.
We didn ‘t have a chance to test the new carbon ceramic set-up as it won ‘t be available on the M6 convertible until later this summer. But the standard steel stoppers were more than adequate under the extreme duress of hours of mountain roads.
All launch cars were equipped with the standard 19 ” wheels and non-runflat Michelins. We asked BMW NA M Boss Matthew Russell about the choice of the 19 “s over the otional 20 ” for the press cars – the latter surely to be what most M6s are equipped with. The reason comes down to weight. The 19s offer better performance and comfort due to less weight and an inch more tire sidewall.
Currently the M6 Convertible (and Coupe) are only avaialble with the exceptional 7 speed DCT transmission. However, Mr. Russell made it clear that, if there ‘s demand they ‘d love to offer the six speed manual destined for the F10M M5 in the M6 Coupe and Convertible. And if I were a betting man I ‘d guess that wouldn ‘t be until late 2013.
The M6 Convertible interior is incredibly well executed as all 6 Series are. In fact I ‘d put this above Audi ‘s best in both design and material quality. Perhaps a first for BMW. On top of all of this BMW M brings a few exclusive featuring in the cabin. Aside from the M logos everywhere, there ‘s theM Instrument Cluster with M Driving Dynamics display and M specific HUD. There ‘s always the standard carbon fiber trim which can be deleted in favor of several different wood trims.
Perhaps the biggest interior change is the new stand-out M steering wheel. The last ten years of M steering wheels have been a series of big and bulky designs that seemed at odds with the purity of the brand and the sporting nature of the cars. And now we have what is, for intents and purposes a revelation in steering wheel design for M. Starting with the impossibly small round center and extending to the thin three spokes M designers have clearly been inspired by the classic steering wheels of the 80 ‘s while pushing the material quality and design further than before. As the centerpoint of the interior it serves the M6 incredibly well and defines the cockpit as a serious place for serious drivers.
On the steering wheel BMW has placed not one but two M buttons that allow the driver to tailor different modes of mischievousness. Everything is customizable three ways; DSC, engine Response, damper stiffness, steering boost and of course the M-DCT Drivelogic settings. It ‘s both a simplier and more well rounded system than the previous M6 and with the two M buttons, a bit idiot proof.
On the highway comfort settings work best. But on the mountain roads north to Santa Barbara we found that the most extreme settings were surprisingly tolerable. That said the addition of 20 ” wheels may make the Sport Plus suspension setting less than ideal on some roads. The only setting that felt a bit too extreme for the road was the DCT shift speed turned up to three.
At a base price of $113,995 you ‘d expect greatness. And with the M6 Convertible you get that and a bit of brilliance thrown in. BMW M has created a car that is smarter than it ‘s driver 99.9% of the time. Not counting the M range of SAVs, the M6 Convertible is as far away as ever been from the docile and nimble E30 M3. Which is prescily where it needs to be. This is a GT car. Unapologetic and unashamed it can devour highway miles better than any M car ever all while generating speed that would have seemed unfathamble a decade ago. And yet it also contributes less CO2 to the atmosphere and goes longer on a gallon of fuel.
Is it perfect? It could certainly weigh less. And there is less rigidity than I would personally like. But with the top down and the S63Tü making evil noises all is forgiven. And all is right with the world.