Petrol vs. Diesel – Which is the More Efficient and Recommended Engine?

Whether to purchase diesel or petrol car, is an old debatable question that doesn’t have a simple answer. So, if you want to reach a specific decision of buying a petrol Vs diesel car, consider taking into account the following factors.

Petrol vs Diesel – Which is the Best?

Before delving deeper into the explanation of the diesel and petrol engine, it’s important to know, from where it all started.

Getting to know the petrol engines, they were the first to be used in the automobiles. While the diesel engines were mainly used for commercial purposes like in trucks, ships, or buses. Fundamentally, not much has changed with the use of petrol engines but the same cannot be said for diesel engines. As, they have proved their worth in the cars, as well.

So, now if you’re ready to know about the factors determining the better engine, let’s get started!

1. Which Type of Engine is More Efficient-Petrol Vs Diesel?

In order to find the better engine out of petrol Vs diesel, in terms of efficiency let’s consider the following aspects, first.

Fuel Burning

Fuel burning in diesel engine is much slower than the petrol
Diesel engine burns much slower than the petrol. Source: FRED LUM / The Globe and Mail

A standard diesel fuel has approximately 38.8 Mega Joules of Energy/litre while the petrol yields 34.8 Mega Joules of energy/litre. This means, for producing an adequate amount of energy to run a car, diesel burns much slower than the petrol. As a result, the mileage of the car increases, if it uses diesel instead of petrol.

Compression Ratio

Firstly, here it’s important to note that engine’s efficiency is directly proportional to its compression ratio.

Compression Ratio ∝Production of Mechanical Energy ∝ Engine’s Efficiency

This means, if the compression ratio is high of a fuel, it can convert a large amount of chemical energy into the mechanical ones.

Thus, when the concept is introduced in petrol and diesel fuel, it has been observed that diesel yields more efficiency and mileage. With the standard compression ratio of 20:1, it produces more mechanical energy than the petrol with 10: 1 or 12: 1(standard).

      SEE MORE:

Torque Value

The diesel engine can develop higher torque value than the petrol one. But, what exactly, is it?

Well, the torque is actually responsible for determining the turning force required to drive away the vehicle. In simple words, when a high value of torque is produced at low RPM, this means you can increase the engine speed without wasting much of the fuel.

Better engine out of petrol Vs diesel
Decision of buying a petrol Vs diesel car. Sami Sarkis / Getty Images

2. Which Type of Engine is More Powerful-Petrol Vs Diesel?

Here, the petrol engine wins, as it has lighter parts than the diesel engine. That further allows for the high Revs, when the engine is operated.

Thus, it results in the more performance efficient engine in terms of petrol than the diesel.

3. Which Type of Engine is More Recommended?

Other than, all the above-defined factors, when the diesel and petrol engines are compared based on the cost of fuel, car, and maintenance, the story is somewhat different.

We all are aware that the price of diesel fuel is far less than that of petrol. This is indirectly related to the prices of the car. In other words, diesel cars are costlier than the petrol vehicles. Moreover, the maintenance cost of a diesel car is far higher than the one needed for the petrol-vehicle.

So, if most of your work is on motorways or you have to drive a long distance daily, consider purchasing diesel cars. Or, else if your mileage is lower or you drive locally often, go for the petrol cars.

 Al about petrol Vs diesel engine
Choosing out of petrol vs diesel engine. Source: TW White & Sons

Finally, now when you are aware of the pros and cons of the petrol Vs diesel engine, hope you can select the vehicle that suits your requirements. No matter, whichever vehicle you choose, don’t forget to ask the maintenance tips manual for the same.