What is the difference between 98 and 95 gasoline?

[LilyAnn]

They differ in anti-knock combustion capability and isooctane value. Below are relevant introductions: Introduction to fuel anti-knock property: The anti-knock property of gasoline refers to its ability to avoid detonation when burning in an engine, which is a major performance indicator of gasoline. Strong anti-knock property allows the use of higher compression ratio engines, thereby increasing engine power, reducing fuel consumption, and improving engine economy. Introduction to isooctane: It is an isomer of octane. Isooctane exhibits good anti-knock properties when burning in internal combustion engine cylinders, serving as a standard for gasoline's anti-knock rating with its octane value defined as 100, making it an excellent engine fuel.