Awaited has arrived, version of the BMW 320d EfficientDynamics goes on sale this month (March 2010). It’s as per the regular 320d, unless you’re so into your diesel 3 Series that you can tell that this one rides 15mm lower than the 320d SE. It has low rolling resistance tyres too, contributing to a slightly lower drag coefficient, and the gear ratios are different.
But, compared to the standard 320d, this emits 19g/km less CO2, boasts 10mpg better combined consumption, has 22lb.ft more torque and there’s a fiver in the price difference. Impressed? So are we. Even the 0-62mph time is only 0.1 seconds slower, despite losing 13bhp. It lists at £27,280.
When driving this car, the only noticeable compromise over the standard 320d from the driver’s seat is a noise penalty from the engine at higher revs. But it loses in smoothness and refinement at the top end; unlike most BMWs, this is not one that you’ll particularly enjoy revving.
In essence, a set of sprung weights on the flywheel smooth out the vibrations at low revs – the vibrations that make you feel you’re about to stall and so cause you to change down a gear. It means the car can happily sit at very low revs without the associated driveline vibrations, so you change gear less, keeping the engine speed low, thus improving economy.
However, let’s not belittle the achievement here. This 320d might be a little rough around the edges, but it’s hardly noisy, has all the flexibility of the very flexible standard car, yet boasts genuinely supermini-rivalling economy. BMW could justifiably have charged more for it, but hasn’t. Hats off for that. Plus you’ll annoy the taxman.
