Press Release
Page 1: Overview
Page 2: Engine
Page 3: Design/Suspension
Page 4: Safety/Pricing
High Performance Diesel Engine
Based on the latest Mercedes-Benz technology, the CRD engine is fitted with Bosch high-pressure fuel injection (1600+ bar), a variable geometry turbocharger, four valves per cylinder with dual overhead camshafts, and Piezo injectors with a 0.1 millisecond response time. The new engine, which has also just been made available on the Sedan, meets Euro 4 emission standards and will include an integrated diesel particulate filter. Maximum power is 160 kW and peak torque is 510 Nm from just 1600 rpm.
For this powertrain, the choice of materials, design, fuel injection and engine management system reflects the state of the art engineering adopted during its creation. The 3.0-litre V6 CRD features an aluminium block with cast-in grey iron cylinder liners, which make a major contribution to weight reduction. As a result, the new V6 weighs only 208 kg.
The diesel engine is an exceptionally smooth running power unit due to enhancements such as low-friction valve gear, larger bearings for the crankshaft, connecting rods made from a new alloy and a counter-rotating balance shaft between the cylinder banks. A quick-start glow system shortens preheating time to just a moment, so that the diesel is nearly as quick to start as a petrol engine.
The 3.0-litre V6 CRD engine embodies third-generation common-rail technology. The result is a reduction in fuel consumption, exhaust emissions and combustion noise. Piezo ceramic fuel injectors operate much more rapidly and precisely than previous solenoid valves, and ensure a particularly finely metered fuel supply to each cylinder. Their crystalline structure allows the fuel injection to be accurately adjusted to match current load and engine speed. The number of fuel injections per power stroke has been increased from three to five, at a peak pressure of up to 1600 bar.
The engine was developed as a ‘one-box-concept’ with the cylinder block, add-on components and ancillary units forming a uniquely compact power unit. The camshaft bearings are integrated into the cylinder heads and cylinder head covers, which saves space and cuts noise. The four camshafts are driven by a tried-and-tested double-bush timing chain system which also operates the balance shaft and high-pressure fuel injection pump.
Four additional features are key to the outstanding performance of the 3.0-litre V6 CRD engine. A Variable Geometry Turbocharger (VGT) uses electronic adjustment to rapidly and precisely vary the angle of the turbine blades to maintain charge pressure over a broad range of operating conditions and enable the engine to generate high levels of torque even at low engine speeds. This turbocharger is combined with a downstream intercooler which reduces the temperature of the compressed (heated) air by up to 95 degrees Celsius, allowing a larger volume of air to reach the combustion chambers. A newly developed valve control system for the 24 valves reduces both friction and moving masses. Electronically controlled intake port shut-offs adjust the turbulence of air entering the cylinders to optimise the combustion process and ensure three benefits – more power, lower fuel consumption and lower exhaust emissions.
For the 3.0-litre V6 CRD unit, a W5A580 fiv
