BMW's next M3 to go AWD

BMW’s next-generation M3 will take a leaf out of the new M5’s book, slashing sprint times with all-wheel drive and bringing water-injection out of the margins and into the mainstream.

With the redesigned G20-generation 3 Series sedan due in 2019, our sources say M is already cramming its version full of body stiffening, extra power and more grip.

It will retain a 3.0-litre twin-turbo inline six-cylinder powertrain, but ditch the current model’s dual-clutch transmission for an eight-speed automatic unit.

Critical to its improved straight-line sprint time will be the M3’s first all-wheel drive system, which will be offered alongside the standard rear-drive model and will feature rear-biased torque delivery that M hopes will retain its traditional rear-drive feel.

It’s going to need all of that grip to channel the engine’s rumoured 368kW (a neat 500 horsepower) and 600Nm of torque as it carries over most of the powerplant from the wild M4 GTS, though with more production-friendly engineering.

The water-injection system is an innovation that M first trialed on the M4 that it has deployed as the MotoGP safety car for years now.

Water is sprayed into the inlet manifold to cool it down, and such is the cylinder heat that it then evaporates before combustion begins. This reduces the chances of ‘knocking’ or pre-igniting, which allows M to raise the turbo boost safely.

The G20 M3 will use a direct water-injection system, upgrading the indirect multi-point injection system used in the GTS, and its compression ratio will jump to close to an unheard of 11.0:1.

While there’s no word on mild-hybrid power, it seems likely to join the powertrain in some form, because the G20 M3/M4 will already have a 48-volt electrical system to help boost the speed of its two turbochargers, both adding boost and shrinking throttle response times.

The powertrain will be transferred to other existing M models in time when BMW replaces the G22 4 Series Coupe (which, astonishingly, found its way into the UK’s top 10 sellers last month) and the G23 4 Series Convertible.

The odd one out of the next 3 and 4 Series models will be the Gran Coupe, which will instead be delivered as an all-electric car.