Far from a relic

摘要

For a given engine displacement, for example 8 1 or 10 1, a diesel engine's compression ignition system allows more air to be used in the combustion process compared with a similarly sized petrol engine. This greater amount of air allows more fuel to be used and results in more power generated for a given engine displacement, compared to a petrol engine. Recent fuel injection system advances now allow electronically controlled direct fuel injection. These fuel systems replace the traditional mechanical system and result in more precise control of the fuel injection process. Advantages of these new systems include increased power, lower noise and fuel consumption as well as improved engine response. Also, because these systems ensure that the fuel is burnt very efficiently, the engines create fewer emissions, thereby reducing their environmental impact. Naturally aspirated, non-turbocharged engines use only the quantity of air that is drawn into the engine from the piston movement. The use of a turbocharger or supercharger allows more air to be forced into the engine. Again, diesel's compression ignition system high compression ratio allows for a higher level of turbo charging than is possible with spark ignition engines. This higher quantity of air allows more fuel to be used, resulting in more power.