Evolution is a good thing!

The BMW 520d Efficient Dynamics Saloon has a combined economy figure of 62.8 mpg and emissions of just 119 g/km CO2, it’s a statement of fact!

Going down the history lane, some ten years ago the BMW 520d returned 47.9 mpg along with 156 g/km CO2. A drop in emissions from 156 to 119 g/km CO2 would be have been a dose enough if the rest of the performance figures had stayed the same, but of course you know with BMW, you get overdose because even they have also been massively improved.

The ten year-old 530i Sport Auto with the 520d EfficientDynamics manages just 26.4 mpg and emits 257 g/km CO2. This is more than double the emissions of today’s 520d ED. Yet today’s 520d ED has similar performance figures to that 530i; with a power output of 184 hp and torque of 380 Nm, it can reach 144 mph, with a 0-62 mph time of 8.2 seconds.

So what are the downsides? There must be some compromise in the driving experience? The 520d ED is likely to spend much of its time on motorways, and I am yet to know of a better car to lap up such distances with such efficiency. It has an excellent ride, it’s quiet, refined, comfortable, and has all the luxuries that you’re likely to want. Everything about the car just works perfectly – from the high quality interior controls to the smoothly-shifting six-speed manual gearbox (with the exception of reverse, the selection of which always seems a bit of a fight on manual BMWs).

The 520d ED is also enjoyable to drive on roads other than motorways; on sand roads the rear-wheel drive chassis, which allows the front wheels to steer rather than also having to drive, is in its element.

Of course another major advantage is that you’ll be able to drive for weeks before having to pull into a filling station to fill up.

Although the 520d ED only has one range of alloy wheels to choose from, all of which result in emissions of 119 g/km CO2, the rest of the 5 Series range has three ‘categories’ of alloy wheels, which can result in up to three different levels of economy and emissions. For instance, although BMW quotes emissions of 129 g/km and 57.6 mpg for the ‘standard’ BMW 520d, the official technical specifications show that these figures can drop as low as 125 g/km along with 58.9 mpg with another category of alloy wheels. Also, these figures can improve even further with automatic rather than manual transmission.

So apart from the wheels and tyres, which vary from the standard 520d, but not enough for the average person to notice, what else is different?

Getting technical, the BMW 520d ED has a dual mass flywheel, with springs between the two parts, along with Centrifugal Pendulum Absorbers. This probably means nothing to most people, but it has a simple purpose – to allow the driver to use a higher gear at lower revolutions (revs) without any engine vibration through the drivetrain. The car also has a longer final drive ratio, ie. longer gearing – again to reduce engine revs at higher speeds. Driving at lower revs should mean better economy.

In addition, the 520d ED comes with BMW’s new ECO-PRO Mode. This is one of the three driving modes that you can choose from using the ‘Drive Performance Control’ toggle switch, along with Comfort and Sport. The car is set up to start off in ECO-PRO Mode, which adjusts the engine mapping, throttle sensitivity, and the amount of power consumed by electrical ancillaries including climate control and heated seats, in order to consume less fuel. You can feel the muted throttle response in this mode; swapping to Comfort or Sport makes the throttle respond in a more conventional, reactive way.