There are a number of factors that affect the thermal efficiency of a petrol engine, including:
* The engine design: The design of the engine, including the type of combustion chamber, the number of valves, and the camshaft profile, can all affect the thermal efficiency.
* The fuel mixture: The air-fuel ratio of the fuel mixture can also affect the thermal efficiency. A richer mixture (more fuel, less air) will produce more power, but it will also be less efficient.
* The engine temperature: The temperature of the engine can also affect the thermal efficiency. A hotter engine will be more efficient, but it will also be more likely to overheat.
* The load on the engine: The load on the engine, such as the weight of the vehicle and the speed at which it is traveling, can also affect the thermal efficiency. A heavier load will require more power, and this will reduce the thermal efficiency.
In general, the thermal efficiency of a petrol engine is relatively low. This is because a significant amount of heat is lost through the exhaust gases and the cooling system. However, there are a number of ways to improve the thermal efficiency of a petrol engine, such as using a turbocharger or supercharger, using variable valve timing, and using a leaner fuel mixture.
