Thursday 18 February 2010

MERCEDES-BENZ DELIVERS MORE POTENT, THRIFTY DIESELS


Mercedes-Benz is quite serious about being blue and fuel-efficient. So serious that they have launched the latest-generation diesel powerplants to the South African market. The two concerned models are the C220 CDI BlueEfficiency and the E250 CDI BlueEfficiency. Don’t’ let the nomenclature fool you though; both engines displace the exact same volume at 2.1-litres. But they are quite special in a number of ways.

First off they use the latest common rail diesel system with Piezo-injection technology and two turbos placed in sequence. One of those turbines is a small unit capable of spinning at up to 240 000rpm (no typo here) but doesn’t often do so because of a bypass duct that reduces its speed. The second is bigger and only takes over once sometime in the mid-range of the rev band. Why they do this is to kill what is called turbo lag, you know, the one or two second time delay you feel after planting right foot through the floor. Thanks to this combination the C220 CDI BlueEfficiency and the E250 CDI BlueEfficiency make their respective torques at very low rpms each.


Speaking of torque, let’s look at exactly how much power is derived from these two engines. The C220 CDI BlueEfficiency is capable of launching 125kW between 3000rpm and 4200rpm. Its peak torque is 400Nm borne between 1400rpm and 2800rpm. Mated to it is a 5-speed automatic gearbox, which is an interesting choice given the fact that Merc’s 7-speed automatic is much more fuel efficient-capable. Nevertheless it can help the car go from 0 – 100km/h in a claimed 7.65 seconds and top off at 231km/h. Average fuel consumption is rated at between 5.8 and 6.4 litres per 100km. If achieved in real world conditions it would give you about 800km from a full tank of diesel. C02 emissions are between 153g/km and 167g/km.

I can’t attest to any of these figures for sure, but to say the pull off the line from the C220 CDI is gratifying to say the least. Smooth changes are the order of the day, although I still say the 7-speed would have been even smoother. I’m quite certain we covered over 300km on one quarter of a tank, although most of our drive was confined to the open road.

In taking the keys to the E250 CDI BlueEfficiency my heart was excited by the prospect of planting 500Nm of torque on the tarmac. That’s right, 500Nm of raw pull from a four-cylinder engine! Maximum power is 150kW at 4200rpm. All that torque is available from 1600rpm to 1800rpm, a relatively short travel but highly effectively nonetheless. Takeoff from 0 – 100km is said to go by in 7.8 seconds while a top speed of 240km/h can be attained on a flat surface. Again, cream is the word when it comes to the powertrain. Drivers can choose between the default Comfort mode where the car will take off in second gear and progress through the gears in a civilised fashion. Sport mode allows for more swift takeoffs and sharper changes but still keeping things silky.

Apart from the new engines the two cars are equipped with the usual luxury items including power steering, leather seats, climate control, rain sensors, multi-function steering wheel and a 6-CD integrated changer.

Mercedes-Benz has shown some of its cards as far as the government’s new upcoming fuel tax is concerned, and it looks like a full house.


Pricing
C220 CDI BlueEfficiency sedan (R387 000)
C220 CDI BlueEfficiency Estate (R396 000)
C250 CDI BlueEfficiency (R517 000)

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