Leaner, faster, 4WD M5
Sixth-gen supersaloon with groundbreaking all-wheel drive finally shows its face
with the front axle only coming into play when the rear tyres lose grip. The next stage is M Dynamic mode, which puts the drivetrain into ‘4WD Sport’. In this setting the electronics allow more slip from the rear axle before sending drive to the front.
Finally, there’s ‘2WD’, only available with all traction and stability systems switched off. BMW says it is designed ‘for track use by experienced drivers’. With 592bhp and, perhaps more pertinently, 750Nm of torque, ‘2WD’ mode and a wet roundabout could certainly prove interesting…
BMW M has yet to confirm an official kerb weight, but engineers have told us that the new car should be slightly lighter than the outgoing F10M model – and that’s despite the additional 60kg-or-so of four wheeldrive hardware. The M department has adapted technology used in the M760i, utilising that car’s transfer case with its electronically controlled clutch, along with the Active M Differential from between the rear wheels of the M3/M4. The centre diff can range from 100 per cent open (essentially rear-wheel drive) to a 50:50 split, and is said to be all but seamless in its operation.
The new M5 is powered by the same twin-turbo 4.4-litre V8 as before, although as you’d expect it has been given a thorough update. With revised turbos, increased direct-injection fuel pressure to 350bar and improved lubrication and cooling systems – the former including a variable pump designed for ‘racetrack applications’ – the new engine comfortably exceeds the 552bhp and 679Nm of the old car and the 567bhp of the previous Competition Package model.
A significant change to the M5’s drivetrain is the switch from a twin-clutch M DCT gearbox to an eight-speed ‘M Steptronic with Drivelogic’ torque converter. Its operation is governed, as with other aspects of the M5’s behaviour, by modes – there are three, along with Efficient, Sport and Sport+ for the engine – and gears can be changed manually via paddles on the steering wheel or with the gear selector. BMW M engineers claim there is no loss of performance with the Steptronic