This G20-generation 330e is the second 3 Series with that derivative identity. It’s considered by BMW engineers to be the first 3 Series designed from ‘clean sheet’ to accept plug-in hybrid power, rather than being adapted for it. The difference that makes isn’t huge, but it has allowed the car some important technical gains.
Just like the last one, this 330e has a longways-mounted 181bhp 2.0-litre turbocharged petrol engine that drives the rear wheels through an eight-speed automatic transmission.
Just like the last one, it has an AC synchronous electric motor sandwiched between that gearbox and the back of the piston engine, which is connected via a system of electronically controlled clutches.
The electric motor can contribute up to 111bhp into the driveline (up about 25% on the last car) and it can power the car by itself at speeds of up to 87mph. The total system output is now 289bhp with both pistons and electrons working flat out, with peak combined torque pegged at 310lb ft.
Further aft in the car, greater redesign has occurred. Whereas the previous, F30-generation 330e had a conventionally placed fuel tank under the back seat cushions and a 7.6kWh drive battery and power inverter living outside of the wheelbase and under the boot floor, BMW has switched the components around in this new one.
The latest 330e’s 12.0kWh lithium ion drive battery is sited under the back seats and its 40-litre fuel tank is to be found immediately above the rear axle. Usable ‘net’ battery capacity in the 330e has therefore almost doubled (from 5.4kWh to 10.3kWh) and electric range has risen significantly to up to 37 WLTP-certified miles, depending on which particular trim level you choose.
At the same time, the car’s major masses are better located, either within the wheelbase or at least as closely as possible, than they used to be. Suspension is via struts up front and multiple links at the rear. Kerb weight is claimed to be 1740kg unladen, which makes this car only 80kg heavier than the 330d xDrive.