Apr 12, 2006
- Torque: 18 percent more from the four-cylinder diesel engines
- Output: 26-percent increase for the new E 500
- Economy: average consumption for all models only nine litres per 100 km
Six of the ten engines for the new generation E-Class are new or further developments. The main goals of this initiative were to increase torque and output even further while maintaining a favourable fuel consumption, and Mercedes engineers have successfully achieved this. The output range of these engines now extends from 100 kW/136 hp to 378 kW/514 hp and is therefore significantly greater than previously (90 kW/122 hp to 350 kW/476 hp). Accordingly the E-Class is more than just a little ahead of its competitors in most displacement and output classes.
Particularly the diesel engines enter new dimensions in terms of torque: the maximum torque of the four-cylinder units is increased by up to 18 percent, and the V6-engine in the 320 CDI now delivers around six percent more torque.
Despite this considerable increase in output and torque, the fuel consumption of the models E 200 CDI to E 500 remains at the exemplary level of the preceding series, with an average of just nine litres per 100 kilometres. One third of the 27 model variants in the new generation E-Class consume less than eight litres of fuel – an impressive figure which documents another important quality attribute of the E-Class in addition to safety, comfort and driving pleasure, namely economy.
The exemplary petrol or diesel consumption of the Saloon and Estate models not only makes itself felt in the size of fuel bills, but also ensures greater independence when travelling. Very few refuelling stops are necessary even on long journeys. The E 320 CDI has a range of around 1100 kilometres on a full 80-litre tank, for example. The E 280 CDI, which is equipped with an 80-litre tank as standard in the ELEGANCE and AVANTGARDE lines, is even able to manage 1150 kilometres on a tankful. This roughly corresponds to the distance from Berlin to Venice, or Berlin to Paris.
The large-capacity fuel tank included as standard for the V6 and V8 models is available as an optional extra for the four-cylinder models and the E 280 CLASSIC.
Four-cylinder diesel engines: perfected to the last detail
Thanks to their economical yet powerful engines, the E 200 CDI and E 220 CDI are among the best-selling models in the E-Class. In the new generation of this Mercedes model series, these four-cylinder variants offer even more diesel driving enjoyment. The engineers in Untertürkheim have improved these direct-injection units in several respects, modifying more than 90 components in total. Some examples:
- Larger oil spray nozzles supplied from a more powerful oil pump improve piston-cooling.
- Shorter conrods and higher pistons have made it possible to reduce the compression ratio from 18.0 to 17.5, thereby increasing engine output.
- The cylinder head has a new cooling concept for improved performance characteristics.
- The air ducting in these engines has been improved in terms of pressure losses and noise characteristics.
- The intercooler and turbocharger have been modified to improve the responsiveness of the CDI engines in the lower engine speed range, as well as reducing nitrogen oxide emissions even further.
- The injection system, which operates on the efficient common-rail principle, has been developed further, with more advances in demand-related fuel metering e.g. through installation of a knock sensor. This results in noticeably reduced combustion noise.
- The exhaust gas recirculation system is equipped with a cooling system which is activated by a by-pass as required.
- Ceramic glow plugs reaching higher temperatures than the previous metal glow plugs improve the starting and cold running characteristics of the diesel engines.
- Balancer shafts in the crankcase, which counter-rotate at twice the speed of the crankshaft, compensate inertia forces and ensure the smoothness and quietness typical of a six-cylinder engine. This Lanchester harmonic balancing is now also a standard feature in the E 200 CDI.
As a result of this extensive package of improvements, the CDI four-cylinder units generate over 13 percent more output and around 18 percent more torque.In figures: the new E 200 CDI (Saloon) now has an output of 100 kW/136 hp and develops its maximum torque of 340 newton metres from 2000 rpm. The fuel consumption remains unchanged at just 6.3 litres per 100 kilometres. The new E 220 CDI (Saloon and Estate) develops a maximum output of 125 kW/170 hp and makes its maximum torque of 400 newton metres available from 2000 rpm. The Saloon is happy with 6.3 litres of fuel per 100 kilometres, while the Estate consumes 7.1 litres.
In addition the engineers in Stuttgart have improved the torque characteristics by raising the engine cut-off point to 5000 rpm, enabling drivers to make fuller use of the gears.
|E 200 CDI||E 220 CDI|
|Cylinder arrangement/ |
valves per cylinder
|Compression ratio||17.5 : 1||17.5 : 1|
|Max. torque Nm at rpm||340/2000||400/2000|
|Fuel consumption |
|6.3 (Saloon)||6.3 (Saloon) |
Six-cylinder diesel engines: E 320 CDI with 540 newton metres of torque
The diesel range for the E-Class continues to include the new V6-engines with 140 kW/190 hp and 165 kW/224 hp, as well as the muscular V8 direct-injection diesel whose 231 kW/314 hp makes it one of the most powerful engines in its class. The maximum torque of the E 320 CDI has increased from the previous 510 to 540 newton metres. This is already available from 1600 rpm, and remains constant up to 2400 rpm.
The maintenance-free particulate filter system developed by Mercedes-Benz is standard equipment in all diesel models of the new-generation E-Class.
Supercharged four-cylinder engine with 12.5 percent more output
More output and higher torque with the same fuel consumption – in the new-generation E-Class, Mercedes-Benz has also achieved this engine development goal in the case of the four-cylinder units of the E 200 KOMPRESSOR. A modified engine management system, a more dynamic supercharger and improved pistons have increased the output by 12.5 percent to 135 kW/184 hp. At the same time the maximum torque has increased from the previous 240 to 250 newton metres from 3500 rpm.
As a result the E 200 KOMPRESSOR accelerates from standstill to 100 km/h half a second more rapidly than before (9.1 s), with a six km/h higher maximum speed (236 km/h).
|E 200 KOMPRESSOR|
|Cylinder arrangement/ |
valves per cylinder
|Compression ratio||8.5 : 1|
|Max. torque Nm at rpm||250/3500-4000|
|Fuel consumption |
|8.2-8.8 (Saloon) |
Eight-cylinder petrol engine: new high-tech power unit for the E 500
Adopted from the S-Class, the newly developed V8-engine makes the E 500 the most powerful eight-cylinder model in its displacement class. This power unit develops 285 kW/388 hp from a displacement of 5.5 litres, an increase of more than 26 percent versus the previous V8. At 530 newton metres the torque also comfortably exceeds the maximum for the preceding engine by around 15 percent. This high level of torque is available from 2800 rpm and remains constant throughout a wide engine speed range up to 4800 rpm. Ideal conditions for powerful acceleration and fast intermediate sprints:
- The new E 500 accelerates from zero to 100 km/h in 5.3 seconds, and is therefore 0.7 seconds faster than the previous eight-cylinder Saloon.
- In third gear, the V8 Saloon sprints from 60 to 120 km/h in just 5.3 seconds.
The fact that the combined NEDC fuel consumption of 11.5 litres per 100 kilometres has remained at the level of the preceding model, despite a higher output and more torque, clearly demonstrates the efficiency of the up-to-date concept and high-tech features of the new Mercedes eight-cylinder unit.
A crankcase of diecast aluminium with low-friction aluminium/silicon cylinder liners is the solid and durable basis of the new Mercedes eight-cylinder engine. It houses a five-bearing, forged steel crankshaft with induction-hardened main and big-end bearings. The conrods are also of forged steel, with specific areas milled away to make them around one fifth lighter than the conrods of the previous V8 engine for the E-Class.
Shifting camshafts for a perfect gas cycle and higher torque
Mercedes engineers have used an intelligent valve control concept system in the new V6 engine of the E 280 and E 350, achieving remarkable progress and a major contribution to the good performance characteristics and low fuel consumption of the unit. In addition to four-valve technology, continuously adjustable intake and exhaust camshafts ensure that the cylinders are optimally supplied with fresh mixture. The valves are opened at precisely the right moment in any driving situation, significantly improving the gas cycle in the combustion chambers and reducing energy losses.
In the new eight-cylinder engine the engineers at Mercedes-Benz have optimised the effect of this four-fold, continuous camshaft adjustment by using so-called shifting camshafts.
These control the opening of the exhaust valves and improve the engine’s gas cycle even further. Depending on the ignition sequence, the exhaust cams are designed in such a way that the valves open at different times during the exhaust cycle. This reduces the pressure fluctuations in the exhaust tract which are inherent to a V8 engine, and which lead to an inconsistent residual gas content in the cylinders.
The valve lift on the exhaust sides of the new Mercedes eight-cylinder engine is as follows:
- Cylinders 3, 4, 5, 7: 180 degrees crankshaft with 2 mm valve lift
- Cylinders 1, 2, 6, 8: 190 degrees crankshaft with 2 mm valve lift
The newly developed shifting camshafts improve the torque and smoothness of the V8 engine by ensuring a more uniform residual gas content, a higher knock limit and better cylinder charging in the lower to medium engine speed range. At 2000 rpm, for example, the effective mean pressure is around six percent (10.3 : 11.0 bar) higher than in a comparable engine without shifting camshafts.
Two-stage intake module and tumble flaps for better combustion
In addition, the new V8 features the same technical innovations for situation-related control of the combustion processes that have already proved successful in the six-cylinder engine:
- Two-stage intake module for a controlled air supply depending on the engine load and engine speed;
- Optimised airflow for the best possible engine aspiration;
- Tumble flaps at the end of each intake duct for more complete combustion.
|Cylinder arrangement/ |
valves per cylinder
|Compression ratio||10.7 : 1|
|Max. torque Nm at rpm||530 |
|Fuel consumptio |
|11.5 (Saloon) |
The developers of the new Mercedes eight-cylinder engine have also made a major contribution to fuel economy with a sophisticated heat management system. Coolant circulation is interrupted during the warm-up phase, for example, so that the engine reaches its normal operating temperature more rapidly. This in turn improves the oil flow and considerably reduces friction in the engine. When the engine is warm and under full load, the heat flows are directed in such a way that the engine oil and coolant are always at an optimal temperature. This is ensured by an innovative, electronic map controlled thermostat which is active in all operating situations and adjusts the coolant temperature according to the style of driving and the prevailing conditions. This also enables the heat supply to the heat exchanger in the heating system to be controlled as needed.
Twin catalytic converters und linear lambda control for low exhaust emissions
The emission control system of the new Mercedes eight-cylinder follows a two-stage concept and is therefore highly effective. In addition to in-engine measures such as continuous camshaft adjustment, need-related combustion control by tumble flaps, exhaust gas recirculation and secondary air injection, which ensure low untreated emissions, the new E 500 is equipped with two close-coupled catalytic converters as standard. These consist of two individual monoliths or bricks, each of which is monitored by two lambda sensors: a control sensor and a diagnostic sensor which analyses the exhaust flow in the gap between the two bricks.
This lambda control is linear, which means that the lambda sensors are already active immediately after a cold start, supplying information about the exhaust gas constituents for the electronic control unit of the V8 engine to process when controlling the warm-up phase. This enables the catalytic converters to reach their normal operating temperature more rapidly.
Thanks to its ultra-modern technology and efficient emission control system, the new eight-cylinder engine complies with the most stringent exhaust emission standards currently in force; it also has the potential to meet limits which are planned for the future.