1 | 2The C 180 KOMPRESSOR and C 200 CDI models are both equipped with the six-speed manual transmission with overdrive characteristics as standard. With a ratio of 0.838 : 1 and 0.828 : 1, respectively, sixth gear considerably lowers the engine speed and fulfils a major precondition for fuel-efficient driving.
Useful information: new gearshift and fuel consumption display in the cockpit
A newly developed gearshift display in the cockpit informs the driver when he should change gear to save fuel. Experience gained during the Mercedes-Benz "ECO Training" courses has shown that drivers are able to make average fuel savings of up to 15 per cent with an economical and energy-conscious style of driving - without any loss of driving enjoyment.
In fact "ECO Training" will practically come as standard in the future BlueEFFICIENCY versions of the C-Class: in addition to gearshift recommendations, the instrument cluster features a newly developed display showing the present fuel consumption. This will appear in the centre of the speedometer as an easily legible bar chart. A brief glance at the display is sufficient to tell the driver the current fuel consumption in litres per 100 kilometres. The bar chart responds immediately when the driver changes to a higher gear or takes his foot off the accelerator to use the deceleration fuel cut-off function.
Up-to-date engines: downsized C 180 with the same output
Under the bonnets of the new model variants can be found well-proven four-cylinder engines, which are amongst the bestselling power units in the model range: around one quarter of all C-Class buyers opt for these four-cylinder engines.
For the C 180 KOMPRESSOR Mercedes-Benz has reduced the overall displacement from 1796 to 1597 cubic centimetres, while retaining the same output (115 kW/156 hp) and torque (230 Newton metres). This downsizing of the engine's displacement, combined with measures for optimising the combustion chamber, mixture formation and engine friction, adds up to a total potential fuel saving of 0.35 litres per 100 kilometres.
All in all, the NEDC fuel consumption of the C 180 KOMPRESSOR in BlueEFFICIENCY guise is just 6.5 litres of premium petrol per 100 kilometres. This is 0.9 litres or twelve per cent less than for the standard production model.
The displacement, output and torque of the CDI engine remain unchanged. The package of efficiency measures has enabled the NEDC fuel consumption of the BlueEFFICIENCY version of the C 200 CDI to be cut by 0.6 litres (10.5 per cent) to just 5.1 litres per 100 kilometres. This corresponds to CO2 emissions of 135 grams per kilometre.
Key engine, performance and fuel consumption figures at a glance:
C 180 KOMPRESSOR BlueEFFICIENCY C 200 CDI BlueEFFICIENCY
Displacement 1597 cc 2148 cc
Output 115 kW/156 hp at 5200 rpm 100 kW/136 hp at 3800 rpm
Max. torque 230 Nm at 3000-4500 rpm 270 Nm at 1600-3000 rpm
0-100 km/h 9.5 s 10.4 s
Top speed 230 km/h 220 km/h
NEDC consumption* 6.5 l/100 km 5.1 l/100 km
CO2 emissions 156 g/km 135 g/km
*combined consumption
C 350 CGI: ten per cent more economical thanks to direct petrol injection
As of late 2008, the BlueEFFICIENCY C-Class line-up will be rounded off by the world's first petrol engine with spray-guided direct injection. Cue the new C 350 CGI BlueEFFICIENCY, which is being presented by Mercedes-Benz at the Geneva Motor Show. Despite generating a higher power output and even greater torque, the new model consumes around ten per cent less fuel than the C 350 saloon with the current V6 engine. The C 350 CGI is therefore set to offer a hitherto unrivalled combination of power delivery, agility, safety, economy and environmental compatibility in this vehicle class.
The CGI engine summons up an output of 215 kW/292 hp and 365 Newtonmetres of peak torque at 3000 rpm. 15 kW/20 hp and 15 Newtonmetres more respectively than the current V6 unit with port injection. Thanks to state-of-the-art engine technology, fuel consumption of the C 350 CGI BlueEFFICIENCY has been cut to approx. 8.4 litres per 100 kilometres (provisional NEDC figure), approx. one litre below the figure for the current C 350. As such, the new six-cylinder engine makes a major contribution to reducing carbon dioxide emissions. These significantly improved output and fuel consumption figures are achieved whilst still using cost-efficient premium grade petrol (RON 95).
The CGI unit also offers an impressive driving experience combined with superb economy and environmental compatibility: the C 350 CGI BlueEFFICIENCY takes just 6.2 seconds to accelerate from 0 to 100 km/h and is capable of an electronically limited top speed of 250 km/h (provisional figures).Mercedes-Benz became the first car maker to put spray-guided direct petrol injection into series production in 2006. This technology is markedly superior to the direct injection system with wall-guided combustion used by other car makers, as the Mercedes technology achieves far better fuel utilisation due to its higher thermodynamic efficiency, meaning both reduced fuel consumption and lower exhaust emissions.
The six-cylinder engine demonstrates its particular strengths during stratified-charge operation when the powerplant operates with a high excess of air and is thus very fuel-efficient. In the Mercedes direct injection engine, this favourable lean-burn operation with a stratified charge in the combustion chamber is also possible for the first time at higher engine speeds and load ranges because the engine's combustion chambers are injected with several successive jets of fuel in fractions of a second during each power stroke, thereby substantially improving mixture formation, combustion and consumption. Whereas stratified-charge operation was previously only feasible over a limited partial load range, the CGI six-cylinder engine can now be operated in stratified charging mode over a wider range.
Piezoelectric injectors: enabling lightning fast multiple injection
High-speed, ultra-precise piezoelectric injectors are among the key components of the second-generation direct petrol injection system. The invention of these injectors has spawned virtually all the advances in the spray-guided combustion system. The piezoelectric valves open their injectors outwards to create an annular gap just a few microns wide, allowing the fuel jet to form with a uniform, hollow cone-shaped pattern. Thanks to millisecond switching times, the piezoelectric injectors also permit the multiple injection that promotes lean-burn operation and helps create the ideal conditions for the engine's exemplary consumption figures. A high-pressure pump with downstream distributor and pressure valve supplies the fuel and regulates the amount delivered in accordance with requirements. With a pressure of up to 200 bar, the system develops around 50 times the fuel pressure of a conventional port-injection system.
The combustion system developed by the Mercedes engineers, with multiple, closely spaced injections during each power stroke, also serves to enhance the V6 engine's smooth running and emissions characteristics. Measurements show that untreated emissions (hydrocarbons) are reduced by more than half in the warm-up phase. Active control of injection and combustion also produces higher temperatures in the exhaust manifold, thereby warming up the catalytic converters faster.
The data for the new C 350 CGI BlueEFFICIENCY at a glance:
Displacement 3498 cc
Bore/stroke 92.9/86.0 mm
Compression ratio 12.2
Output 215 kW/292 hp at 6400 rpm
Max. torque 365 Nm at 3000-5100 rpm
NEDC fuel consumption 8.4 l/100 km*
Acceleration 0-100 km/h 6.2*
Top speed 250 km/h**
*provisional figures; **electronically limited
Four-valve technology, variable camshaft adjustment for the intake and exhaust sides, two-stage intake manifold, balancer shaft and an intelligent heat management system with map-controlled thermostat are some of the other technical highlights that the direct injection engine has adopted from the port-injected C 350 engine. The crankcase and cylinder head are made out of aluminium; the cylinders are fitted with low-friction, dimensionally stable liners made out of a lightweight aluminium-silicon alloy.
BlueEFFICIENCY: additional fuel-saving measures
The package of BlueEFFICIENCY measures for the direct-injection petrol unit incorporates further fuel-saving technologies besides. These include the newly developed windscreen made of laminated glass, which weighs around 1.2 kilograms less than before, forged lightweight wheels and low rolling resistance tyres.
The needs-driven and therefore energy-saving control of the power steering also forms part of the standard specification on the C 350 CGI। Finally, Mercedes-Benz has further improved the saloon's very low aerodynamic drag by fitting new, streamlined exterior mirror housings. A variable radiator shutter improves the airflow around the front end and, depending on the driving situation, also allows control of the air supply to the six-cylinder engine in line with requirements.
Related entries:
Mercedes C-Class Estate Revealed
Brabus Mercedes C-Class Wagon
