Preview: 2006 BMW M5 by Henny Hemmes (7/5/2004)
Ungodly power with demigod moves – that’s the promise.
Motorsport fans who hardly recovered from looking at and reading about the jubilant first impressions of driving the BMW M5 saloon beware: there is more excitement coming in the near future with the M6.
The unveiling of the motorsport version of the 6-Series coupe wasn’t even history last month when BMW sent out the invitations for the first media drives of the M6 on the road and on the Ascari race track in the south of
Let’s focus first on the mighty 5.0-liter V-10 powerplant that generates 507 hp. Reminiscent of BMW’s Formula 1 racing engine, it is, of course, more civilized and runs “only” at a maximum 8250 rpm instead of 18,000 rpm. That means the pistons do not have to cover a distance of some 984 inches per second, but “just” 787 inches per second. It also means the difference between an engine that only has to last one race and an engine that has to last the car’s lifetime.
The ten-cylinder develops its maximum output of 507 hp at 7740 rpm, but offers 80 percent of the maximum torque of 383 lb-ft at 5500 rpm. Although the 90-degree V-10 easily reaches the goal of 100 hp per liter, with a weight of 529 lb it can hardly be considered a lightweight engine.
Optimizing the weight of the pistons — they’re cast of high-temperature-resistant aluminum alloy with an iron coating on the surface — is one of the measures taken to achieve even that weight. The connecting rods are weight-optimized as well, as are the single-piece aluminum cylinder heads.
Important for a performance engine like the V-10 in the M6 is the lubrication, so there has been a lot of advanced engineering put into the V-10. A special lubrication system supplies oil under extreme acceleration and in bends where the M6 can easily achieve lateral acceleration of well over 1g. Engineers also had to consider negative acceleration, or deceleration when braking, which builds up to 1.3g.
For better breathing, the V-10 has individual throttle butterflies for each cylinder. The ten of them are choreographed by an electronically-controlled, throttle-by-wire system for immediate response and for adjusting each throttle butterfly individually after evaluating the position of the gas pedal 200 times per second. BMW’s bi-Vanos variable valve timing provides seamless power supply.
To cope with the high engine speeds, high combustion pressure, and high temperatures, the crankcase is very stiff and uses a bedplate design of cast aluminum with cast-iron inlays for optimum stiffness. Another novelty is the ionic current measurement in of the combustion chambers, which provides information about the combustion process in the combustion chamber itself and it provides information on how completely the fuel in a cylinder burns, which is an advantage in meeting the European and American emission regulations and is helpful when diagnosis is necessary during maintenance and service.
Then, there is BMW’s automated manual transmission, the Sequential M Gearbox (SMG). BMW is the first manufacturer that offers such a seven-speed transmission and Drivelogic. It provides both a manual gearshift and an automatic function and shifts 20 percent faster than the previous generation.
The driver can chose a particular gearshift and has a choice of eleven options. The higher the program, the engine speed, and the load, the quicker the gearshift. Six of the options come with the sequential manual shift function (S-mode) ranging from smooth, to dynamic, to high-performance.
In the Sport mode the car has launch control, in which case the DSC has to be switched off. With launch control a less experienced driver can accelerate perfectly from a standstill. All he or she has to do is push forward the selector lever and push the throttle: there is no need to shift gears all the way to top speed.
The other five options of the Drivelogic program are available in the automated D-mode, in which the transmission shifts the seven gears by itself.
SMG also has a safety feature that is that in a critical situation, for instance shifting back on a slippery surface, SMG opens up the clutch to prevent high engine forces being transmitted to the (rear) wheels and causing the car to break traction.
The Integral IV rear axle is made almost completely of aluminum and has been adapted for the high performance levels. Like the M3 and M5, the M6 also comes with a variable, speed-sensing M Differential Lock for optimum stability and traction.
High-performance (huge) brakes with double-piston calipers are carried over from the motorsport arena and provide excellent stopping power. A sensor determines brake pad wear and transmits data to the DSC control unit, which forecasts the lifespan of the pads.
To restrict the weight of the car, BMW used carbon-fiber composite for the roof (like the limited edition M3 CLS), which saves approximately 11 lb. The front and rear bumper supports are also made of the carbon fiber composite, which accounts for up to a 20-percent weight saving up front and 40 percent at the rear, which plays a role in the M6’s handling.
The 6-Series already had a lightweight construction with an aluminum front structure, thermoplastic front fenders, and a lightweight trunk lid. Unfortunately the M6 weighs still 3771 lb, but that’s still 99 lb less than the M5 with a 4.3-inch-longer wheelbase.
On the 80-mile long stretch from
After driving the new 7-Series, I am finally getting used to the iDrive system. Setting up the car is quite simple: push the iDrive button in the center console and a menu appears on the monitor. The active damper settings are driver-programmable, as well as the intensity of the DSC skid control, the speed of gearshifts and even the engine power from 400 hp, 500 hp and P500 hp (fast throttle response).
To make it really easy, for those times when you want to have the optimum performance of the M6 instantly, there is the M-button on the steering wheel. Then you have the most power, a minimum of DSC and traction control, and can even disengage traction control completely.
On the two-lane road through the south of
Even on the public roads, sporty driving with the M6 is addictive. But the utmost joy comes at the Ascari race track, an interesting combination of slower twists and fast bends, and a long stretch where you can reach fifth gear just before shifting down to third, and later second gear in the chicane.
I began with the standard M Dynamic Mode, which retains a little bit of traction control. But on the race track that means too much interference, although for people with less experience it is a good starting point. Without traction control the M6 shows its full potential. The shifting is so quick that there is even a little wheelspin if you keep the V-10 at maximum revs. The steering reacts fast and precise as well, and the M6 feels glued to the asphalt. When it does break loose, the M6 is really forgiving.
There is only one tight corner at Ascari where the M6 shows a fair amount of understeer. Being able to shift from the steering wheel gives you even more control and the head-up display adds to that feeling. In the windshield you not only see your speed, which is less relevant on a race track, but you also see a half-circle indicating from left to right the powerband in green, to orange to red. You wanted to shift back from third to second and you see green? It’s no use, as the M6 just doesn’t listen.
There was at least one corner where I realized I wanted the paddles on the steering column, not on the steering wheel. But that is the only point that could be improved, especially if you want to do a fair amount of club racing with this BMW.
With the standard tires — 255/40-19 in the front and 285/35-19 in the rear — the M6 had to be checked each five laps. But the tires lasted well, while for me it was easy to learn to operate this ultimate machine. And when you are at that point, you can make the most of it, and also have fun doing power drifts. You won’t want to stop. I begged to drive the last laps until the track closed, before going back to the public roads. There you realize even more how well BMW has blended the sportscar performance in the M6 with civilized and safe sporty driving in daily life.
The M6 is expected on the North American market in May 2006. If you do not want to wait that long for an M version, you can get the M5 that will arrive in the North American BMW dealerships this fall.
Base price: $85,000 (est.)
Engine: 5.0 liter V-10, 507 hp/384 lb-ft
Transmission: Sequential seven-speed DSG semi-automatic, rear-wheel drive
Length x width x height: 191.7 x 73.2 x 53.9 in
Wheelbase: 113.0 in
Curb weight: 3770 lb
Fuel economy (EPA city/hwy): N/A
Safety equipment: Dual front and side airbags, anti-lock brakes, stability control, stability control, traction control
Major standard features: Automatic climate control, power windows/mirrors/locks, electric rear defroster, 19-inch wheels, cruise control, tilt/telescoping steering wheel, CD changer/MP3 player
Warranty: Four years/50,000 miles