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After five years, the F30-generation BMW 3 Series gains a plug-in powertrain. We find out if it was worth the wait

We’re still at that juvenile stage in the development of the plug-in hybrid car when the good ones often distance themselves from the less good simply because they were designed from a clean sheet to accept items such as drive batteries and electric motors.

The 330e certainly feels that way for the most part, although there are a few compromises its buyer is obliged to make, and one or two sacrifices too.

Having tested the 330e in Sport trim for our earlier group test, I was slightly disappointed by the M Sport’s ride and handling

The car adopts a technical layout that is becoming increasingly common among cars of its ilk, where a combustion engine is hooked up in series with an electric motor and both drive through the same transmission.

Relative to the ‘electric rear axle’ route that other PHEVs take, BMW’s philosophy saves weight, although it may also penalise the car slightly on electric-only energy efficiency and operating range, with more inertia and friction for the electric motor to overcome than it might otherwise have had.

The 330e’s combustion engine is the same twin-scroll turbocharged 181bhp 2.0-litre petrol unit that powers the 320i. But hooked up in train with an 87bhp electric motor, it makes for an identical 249bhp peak as the 330i, as well as 52lb ft more torque than its petrol-only sibling.

That’s the kind of pulling power that ought to present itself in our in-gear acceleration figures – particularly since it’s on tap from just 1500rpm.

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For competitive context, that’s a good 25 percent less pulling power than Mercedes claims for the C350e, but it’s marginally more than you get from a Volkswagen Passat GTE.

Drive battery capacity may be of greater interest to most clued-up PHEV buyers, of course, since that’s the biggest telltale of electric-only range and real-world fuel economy.

The 330e’s 7.6kWh of battery capacity exceeds what you get in a Mercedes C350e, but it’s beaten by the 9.9kWh of a Passat GTE and drubbed by the Volvo V60 D5’s 11.2kWh. But then batteries are heavy and can be very punitive on a car’s ride and handling, as the V60 shows.

The BMW’s are carried outside of its wheelbase, effectively in the spare wheel well; and its high-voltage power electronics take up space where the controllers for BMW’s adaptively damped suspension would otherwise be.

Upshot? Unless you go for SE spec, the 330e, unlike other examples of the 3 Series, can’t be ordered without run-flat tyres, and it can’t be ordered with adaptively damped suspension, either (SE or not).

Whereas the car that won our earlier group test was a Sport-spec example on smaller alloy wheels, our test car here is a 330e M Sport on optional 19in rims and equipped with variable-assistance Servotronic power steering, therefore sidestepping BMW’s optional active-variable-ratio Variable Sport Steering, of which we’ve been critical.