Anonymous sources added that the company is looking at a plug-in hybrid drivetrain to increase performance, as well as meet ever tightening emissions and fuel economy regulations, for the next-generation M3 and, we presume, the M4 too.
The core of the new M3's drivetrain will be a development of the current car's, with a 3.0-litre twin-turbocharged straight-six engine connected to the rear wheels via a either six-speed manual or seven-speed dual-clutch transmission. The engine in today's M3/M4 is rated at 317kW of power and 550Nm of torque.
This setup will be augmented by a mechanically separate plug-in hybrid drivetrain, with either one electric motor for the front axle or an electric motor for each of the front wheels. Lessons learnt from the company's i3 hatch and i8 supercar (above) will be applied to the new M3.
To offset at least some of the increased weight brought about by the new drivetrain and its battery pack, the next-generation M3 will use even greater quantities of carbonfibre.
It's claimed that the new plug-in hybrid M3 will have an electric-only driving range of about 32 kilometres and at least 100Nm of extra torque at its disposal.
Timing for the new M3 has yet to be confirmed, but estimates point to a debut in either 2019 or 2020.