PanterroR
Lap Time Luminary
BMW has been building them for years, but I still fail to see the logic in an M3 convertible. Whether I'm a purist or simply stubborn, I've always felt M cars are about blood-pumping, at-the-limit performance above all else. Coupe-based convertibles, well, they're for trophy wives and boulevard cruisers. The two seem about as well suited for life together as Flava Flav and Brigitte Nielsen. Nevertheless, BMW sees fit to keep marrying the two (M3s and convertibles, that is), and this new version may have me seeing the light: It's the best pairing yet, thanks to the new seven-speed, dual-clutch transmission and a folding steel hardtop.
The traditionalist in me still thinks that all M3s should be shifted manually, but for several years now BMW has offered automanual shifting by way of its Sequential Manual Gearboxes (SMG). These performed the task well enough, but they lacked the sophistication of "real" automatics in around-town driving and felt like victims of mechanical abuse when driven assertively. The problem was in part because they were adapted from conventional manual gearboxes (except for the third generation, which was conceived as an SMG from the get-go), but also because they all used a single clutch to transfer power.
As the name implies, the new M-tuned dual-clutch transmission (M-DCT) uses a pair of clutches — one is responsible for gears 1, 3, 5, and 7 while the other manages 2, 4, 6, and reverse. The marvel of the dual-clutch setup is that the transmission automatically pre-selects the next gear for you, and then simply toggles between gearsets for the shift. It happens quickly and seamlessly and without the torque interruptions inherent a single-clutch setup.
So how does this new tranny help the M3 convertible to become a better M3? Simply put, its range of shifting programs, from imperceptibly smooth and silent to race-ready launch control, endows the M3 'vert with the ability to change personalities at the mere push of a button. You want to put the top down and cruise effortlessly while working on your tan? No problem; just move the stubby little shifter to the right and select "D" for full automatic shifting. But if you get bored with that and actually, you know, want to drive, just flick the shifter or one of the steering wheel-mounted paddles and start shifting manually. You don't even have to worry about rev-matching your downshifts — the ECU will handle that, ensuring you sound like a modern-day Hans Stück in the process.
The additional sensory experience of top-down motoring is the single biggest advantage the M3 convertible has over its coupe and sedan brethren, with the unmuffled chorus of the high-revving 4.0-liter V-8 singing through its four stainless steel exhaust pipes just a few feet behind you. The song, as with any M engine, is composed of layer upon layer of mechanical notes. However, unlike the tinny call of its six-cylinder predecessor, this V-8 practically howls at the road. Second- and third-gear pulls through the entire 8400-rpm rev range are like an amusement park ride. Tunnels practically taunt you to drop to the lowest possible gear and goose the throttle for as long as traffic will allow. The sound of the engine makes drivers as giddy as the 414 horsepower it produces.
Of course, once you raise the steel top, the concert fades to background noise and the ultimate tanning machine transforms into an authentic M3. With the roof in place, the M3 convertible is nearly as quiet and refined as the coupe. And nearly as rigid, too, eliminating what cowl shake is otherwise present with the top down. The fact that it shimmies a bit should come as no surprise considering the convertible gets the same 19-inch wheels and track-tuned suspension as other M3 variants. That it feels so very much like the real McCoy is a testament to BMW's M crew, who didn't detune the car for open-roof duty.
Despite my initial skepticism, I've come to terms with the fact that, with the right hardware, it is possible to build a true motorsport-derived performance car in a coupe-based convertible body. With its new gearbox and folding hardtop, the M3 convertible blends relaxed luxury with all-out performance in a way few cars can. As for Flav and Brigitte, well, I'm still not sure why anyone would want to experience that combination.
Source: MotiveMagazine.com - Motive Quickie: 2008 BMW M3 Convertible
