Diesel Versus Spark Engine Ignition

As you may already be aware of, diesel engines are more efficient than gasoline engines of the same power, resulting in much lower fuel usage. For an efficient turbo diesel, the average is 40% more miles per gallon. The higher compression ratio with diesel engines help to raise efficiency, but diesel fuel also contains around 15% more energy per unit volume than gas.

Diesel engines that are naturally aspirated are far more massive than gasoline engines of the same power for two reasons. First, it takes a larger capacity diesel engine than a gas engine to produce the same amount of power. Essentially, this is because the diesel can't operate as quickly. The rev limit is slower, because getting the correct fuel to air ratio into a diesel engine fast enough is more difficult than a gas engine. The second reason is due to the fact that a diesel engine needs to be stronger to withstand the higher combustion pressure needed for ignition.

Diesel engines also produce very little carbon monoxide as they burn the fuel in excess air except at full loading capacity, where a full quantity of fuel is injected per cycle. They can however, produce a black soot from the exhaust, which consists of unburned carbon compounds.

Often times, this is caused by worn injectors, which don't atomize the fuel sufficiently enough, or a faulty management system that allows more fuel to be injected that can then be burned with the available air.

For commercial use that requires towing, diesel engines tend to have more desirable torque. Diesel engines tend to have their torque peak quite low in their speed range which provides smoother control over heavy loads when starting from rest, crucially allowing the engine to be given higher loads at low speeds than a gas engine.

The lack of an electrical ignition system in diesel engines improves the reliability. The high durability of diesel engines is also due to the overbuilt nature as well as the combustion cycle, which will create a less violent change in pressure when compared to a gasoline type spark ignition engine. Diesel fuel is also a better lubricant than gasoline, so it is less harmful to the oil film on piston rings and cylinder bores - making it routine for diesel engines to go 250,000 miles or more without having to be rebuilt.

For several reasons, diesel proves to be better than spark engine ignition. Diesel engines last a lot longer, they offer more torque, and they are also more reliable. They are also more expensive as well, although you get what you pay for. If you have never owned a diesel vehicle, you owe it to yourself to see everything they offer you - and you'll find yourself a very satisfied customer.