Hello, Guys, this topic answers the big question when it comes to buying a car Petrol or Diesel.
The petrol engine has a four-stroke process, Intake, Compression, Power, Exhaust. The intake process brings the air-fuel mixture into the cylinder, in compression process the spark plug ignites this mixture, power process generates the power, and the exhaust process the gases are released from the cylinder. The pre-mixed air-fuel mixture in the cylinder creates combustion more smoothly. The petrol engine is mostly used for smaller engine cause it is lightweight than diesel
Diesel engines also have a four-stroke process, Intake, Compression, Power, Exhaust. The intake process only brings the air into the cylinder, in the compression process it has a fuel injector which injects fuel in the highly compressed air with high temperature and ignition happens, power process generates the power, and the exhaust process the gases are released from the cylinder. The process of combustion is uncertain hence noisier and vibration, to reduce this the diesel engine requires a more rugged structure which causes it to be heavy.
Power and Maintenance and Fuel Economy
Diesel engines generate more torque and give better fuel economy compared to a petrol engine. The diesel engine generates more torque at low rpm and does not rev as high as a petrol engine. This is because it has a higher compression ratio(16:1 approx) and high generation of cylinder pressure than the petrol engine. Said this the cost for maintaining a diesel car is high, cause there is high wear and tear and the engine parts are costlier than petrol engines, though the running cost is low, if you don’t use your diesel cars regularly, it is not advised to own a diesel car. But definitely if maintained properly diesel engine has more life than petrol cars.
Diesel engines can be easily increased in power with the turbo or supercharger which pulls more air into the cylinder, and installing a turbo or supercharger is less complicated in diesel engine has there is no air-fuel mixture inside the cylinder initially. On the other hand, petrol has an air-fuel mixture together which makes it complicated to use a turbocharger or supercharger.
Talking about the petrol engine they produce more horsepower compared to diesel and they run at higher RPM. Petrol engines are more refined and have less maintenance cost compared to diesel engines. Petrol(Gasoline) engine have low compression ratio(10:1 approx) so low fuel economy and diesel have high-compression ratio so high fuel economy, cause compression ratio is directly related to the fuel economy. Petrol cars cause less maintenance cost, causes less wear and tear and have cheaper parts compared to diesel, though petrol as a fuel is expensive hence more running cost. But petrol cars are advised for those who have low running, and it is ok if you don’t use your petrol car regularly.
Diesel Causes more emission than petrol. The diesel engine produces approximately 13% more CO2 gas per gallon of fuel burned, than petrol per gallon. Diesel produces more nitrogen oxide and releases more dangerous airborne particles. Though the new technology has lowered the emission in diesel engines, higher diesel engines cause more emission.
Petrol emits Carbon dioxide and hydrocarbons which are not good for nature and causes global warming. On the other hand, diesel emission causes health problems and also causes global warming because of the dangerous particles and nitrogen oxide.
So it depends on person to person requirement. According to me if you are looking for a car and use it daily for several miles and have a good fuel economy and also require an instant boost at low rpm you should go for diesel cars. On the other hand, if you do not use your car daily and you like good power overall and want to enjoy driving without any lag, and like to rev high petrol is the choice.
Also published on Medium.