What Does Gasoline Octane Number Mean?
2 Answers
Gasoline octane number refers to the ratio of the actual anti-knock performance of gasoline to that of standard gasoline. The higher the octane number, the stronger the anti-knock performance. Standard gasoline is composed of isooctane and n-heptane. A higher octane number does not necessarily mean better quality. The primary criterion for selecting gasoline octane number for a car is based on the engine's compression ratio. Mixing different octane number fuels together can easily lead to incomplete combustion, resulting in carbon deposits and shortening the engine's lifespan. Gasoline is a volatile, flammable hydrocarbon mixture liquid obtained from petroleum through fractional distillation, cracking, or pyrolysis. At room temperature, it appears as a colorless to pale yellow, easily flowing liquid that is difficult to dissolve in water and highly flammable.
The gasoline octane rating is represented by numbers, indicating the fuel's resistance to knocking, such as the common 92, 95, and 98 grades. Knocking occurs when gasoline ignites prematurely during the compression phase in the engine, which can easily damage internal components. Higher octane ratings offer better anti-knock performance, making them more suitable for high-performance or power-intensive vehicles. I recommend carefully checking the recommended octane rating in your vehicle's manual. Choosing the right grade can improve combustion efficiency, reduce fuel consumption, and extend engine life. Opting for a lower grade may save money but can lead to knocking and accelerated wear. In high-temperature or high-altitude areas, the impact of octane ratings becomes more pronounced, and sticking to the correct choice can help avoid breakdowns and repairs. Don’t compromise on fuel quality to save money—long-term misuse of improper octane ratings can cause your beloved car to retire prematurely.
