These are exciting times for the diesel engine. Diesel technology is advancing quicker than at any other time in its history. The latest diesel engines feature high-tech components like piezo injectors, DPFs, EGR, and advanced computer systems that control all these electro-mechanical gizmos, and allow them to work together. The result is modern diesel engines are more powerful, fuel efficient, quieter, and emit fewer emissions. Diesel engines are on the rise in an automotive industry that was previously dominated by gasoline. Land Rover has recently released a new 272hp V-8 diesel engine in the Range Rover sold in Europe. This new flagship engine, the 3.6L TDV8 diesel, comes from the Ford diesel plant in Dagenham, England, and is the basis for Ford's 4.4L diesel that is set to debut in the '10 F-150.
The TDV8 is the big brother to the 2.7L V-6 engine built by Ford in collaboration with Land Rover, Jaguar, and PSA Peugoet Citroen. The V-6 engine preceded the V-8 by a couple of years and was the first engine produced in Ford's new Dagenham Diesel Center. About 150,000 of the V-6 engines have been built and have several applications in Jaguar, Land Rover, and Peugoet and Citroen vehicles. However, the 3.6L V-8 is used exclusively by Land Rover in its Range Rover and Range Rover Sport vehicles at the moment. We can only speculate as to if and when this engine will appear in other models in the future. Our unofficial sources report that there is a 4.4L diesel V-8 engine destined for the Ford F-150 and Expedition in North America. The latest reports are that the engine has finished development but has been shelved until the market forces Ford to build a 1/2-ton diesel truck. So basically, after Dodge and GM come out with diesel 1/2-tons, Ford will too.
The 3.6L TDV8 is a 90-degree engine, and the block is built using a revolutionary compacted graphite iron (CGI) that offers higher tensile strength than standard gray cast iron. The cylinder heads are cast from aluminum and feature dual overhead camshafts with four valves per cylinder. The cylinder heads feature innovative intake ports that swirl incoming air so that when the air comes in contact with the injected diesel in the combustion chamber, there is a more homogenous mix of air and diesel. This is to ensure that areas of the combustion chamber are neither too rich nor too lean, because either condition can cause piston slap and/or unburned fuel leaving through the exhaust.
The injection system features a high-pressure (more than 24,000 psi) common-rail that feeds incredibly accurate piezo injectors. The piezo injectors are able to inject different amounts of diesel multiple times per revolution. For example, under some operating characteristics, the injector will inject a small amount of fuel into the cylinder as the piston approaches top dead center. This injection will warm the cylinder and soften the cylinder pressure spike when the main injection occurs. The second injection will provide more fuel and provide the majority of the power. The ability to control multiple injections of fuel makes the combustion process more efficient, and reduces injection noise, ultimately reducing the dreaded knock that is associated with diesel engines. Rubber-dampened injector covers also reduce injection noise. The finely tuned injection system is one of the reasons new diesel engines are so much quieter than in the past, and why diesel engines are now being used by luxury automakers.