What's the difference between using 92 and 95 octane gasoline in the three-cylinder Excelle?

[MacCali]

The Excelle uses 92 octane or higher gasoline, and 95 octane gasoline can also be used. The difference is minimal. Here's some extended knowledge about refueling: 1. Anti-knock performance: The difference between 92 and 95 octane gasoline lies not in the fuel quality or purity, but in the anti-knock performance, primarily determined by the octane number. The octane number indicates the gasoline's anti-knock capability. The higher the octane number, the better the anti-knock performance, and the less likely it is to cause engine knocking. 2. Engine design performance: If a car manufacturer recommends using 92 octane or higher gasoline, then using 92 octane is sufficient. There's no need to use 95 octane gasoline, as it won't significantly improve power, fuel economy, or mileage. However, if the manufacturer recommends 95 octane gasoline, it's advisable to use it as much as possible. Using 92 octane gasoline in such cases may indeed increase fuel consumption and reduce mileage because the lower anti-knock performance cannot meet the engine's design specifications.