BMW 320d EfficientDynamics Saloon review (2010 onwards)

What - BMW 320d EfficientDynamics Saloon
Where - Germany
Date - March 2010
Price - £27,245 Available - now
Key rivals - Audi A4 1.6 TDIe, Mercedes-Benz C250 Cdi BlueEfficiency

Summary - the BMW 320d EfficientDynamics Saloon is the greenest BMW ever - and the first junior executive car to emit less than 110g/km CO2. Very green, very clever, but still a fun to drive BMW.

We like - impressive economy with impressive performance, subtle greener driving tactics, exceptional refinement, still great to drive
We don't like - rivals cheaper and roomier (but less efficient), loses a touch of the usual 3 Series sparkle, four-door saloon only so far

Gallery: BMW 320d EfficientDynamics Saloon
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First Impressions
This car's full title, 'BMW 320d EfficientDynamics Saloon', is a bit of a mouthful - and a hell of a boot badge, should Munich ever deign to fit one - so we'd best shorten it a touch.

BMW 320d ED has a nice ring to it, even if it does put us in mind of a psychopathic killing machine from the RoboCop movies, and a 1960s American talking horse.

But this 'Meister' Ed is neither old nag nor several shades of violent death (though stairs could still be an issue). Rather, it is the greenest car that BMW has ever built.

It emits just 109g/km CO2 - an incredible achievement for the junior executive class - and returns a remarkable 68.9mpg according to official EU testing figures.

That's better than any 1 Series, and well ahead of what the likes of Audi's A4 and the Mercedes-Benz C-Class can offer - 129g/km and 127g/km their respective eco peaks at present.

Yet in spite of its planet hugging cleanliness, the 320d EfficientDynamics can still sprint 0-62mph in eight seconds flat, and has a ridiculous 142mph top speed.

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Performance
So, the 320d ED is still a proper BMW - something that's also reflected in the handling, below - and the changes to make it cleaner aren't so much compromise as realignment.

Although the 163hp 1,995cc turbodiesel under the bonnet is of identical capacity to others in the range, the engineers say it's like they've built an entirely new motor.

New turbo, new airflow management and third generation common-rail injection join a wild dual-mass flywheel with 'Centrifugal Pendulum Absorbers'; this last sounds complex - and is - but simply sooths low speed vibration.

The result is 21hp less than the ultimate expression of 2.0-litre 3 Series turbod power available in the regular 184hp 320d, but the same substantial 280lb ft of torque.

As the figures suggest, it still shifts. Yet BMW has cleverly created a car that encourages you to drive more economically. It's a subtle process, too, not a shouty one.

That tricky flywheel makes the engine much more comfortable at low revs, meaning it will happily pootle along in sixth at 1,200rpm without shaking you or your passengers to pieces.

At the same time a longer final drive gear ratio gives the car a much more relaxed demeanour, feeling noticeably less immediate in its throttle responses than the regular 320d.

The upshot of it all is that you end up driving the 320d ED on its low-end torque, rather than revving the nuts off it - great news for real world fuel economy.

Ride and Handling
Marking another difference between the EfficientDynamics and regular BMW 320d models, the ED comes with lowered suspension and aerodynamic alloy wheels in order to reduce drag and further improve economy.

This hasn't really damaged the ride comfort, since the 16-inch wheels are not only an inch smaller, the Michelin EnergySaver tyres are decidedly not run-flats, meaning they have nice compliant sidewalls.

And eco or not, this 3 Series is still a lovely car to drive. The relatively thin-rimmed steering wheel (by BMW standards) and mechanically precise six-speed manual gearbox add tactile delight.

The steering feel and rear-wheel drive chassis balance are excellent - Audi drivers have no idea what they're missing - and compared to other cars in class the 3 Series is now quite compact.

Which only makes it seem even more wieldy and responsive. And although the longer gearing may mean the ED lacks the sprightliness of other 3ers, it will still hustle hard if you ask it.

No compromise green motoring? Perhaps - though the BMW's subtle speed reduction tactics do make it seem a little less exciting than, say, the cheaper Mercedes C 250 CDI with 368lb ft of torque...

Interior
The BMW 320d EfficientDynamics Saloon is, as the name suggest, available only as a four-door. But aside from this compromises are again minimal, as it is based on the regular SE specification.

There is absolutely no reduction in equipment level, so you still get air conditioning, rear parking sensors and BMW's usual solid interior build quality. Not much else we can say here.

Economy and Safety
We've already covered the official fuel economy and emissions figures - 68.9mpg and 109g/km CO2, just to recap. Driving it back to back with a regular 320d, we can also confirm you really should see an improvement.

Another item of note is the gearshift indicator, which suggests the ideal gear for best economy at any given moment. Unlike some rival systems, this isn't obsessed with putting you in sixth as soon as possible.

It will actually encourage you to use lower gears as it deems necessary, so you probably can follow its advice and see a decent return in your miles per gallon figures.

As for safety, you get all the usual BMW electronic aids, six airbags, dynamic brake lights and whiplash preventing front head rests, plus a first aid kit and warning triangle. Nice.

MSN Cars Verdict
You can be as cynical as you like about this kind of car, but there is absolutely no getting away from the fact that the BMW 320d EfficientDynamics Saloon is a very impressive piece of kit.

From the engineering changes to the way it gently coaxes you into driving more sedately, not to mention the class-leading economy and emissions figures, it represents a significant achievement.

Priced at £27,245, it's marginally cheaper than the regular 320d SE (£27,365), if somewhat pricey compared to those equivalents from Audi and Mercedes.

But thanks to its class-leading efficiency, the 320d ED will cost just £35 a year to tax, and you should see real world efficiency gains the others can't match. You have 20 seconds to comply. Etc...

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