Why Do Turbocharged Engines Require 95 Octane Gasoline?

[StDiana]

It is primarily determined by the engine's compression ratio. Below are the reasons why turbocharged engines use 95 octane gasoline: 1. The gasoline octane rating represents the proportion of isooctane in the gasoline. In fact, there is no difference in the quality of these two types of gasoline. The main difference between 92 octane and 95 octane gasoline lies in their octane values. 92 octane gasoline contains 92% isooctane and 8% n-heptane, while 95 octane gasoline contains 95% isooctane and 5% n-heptane. If a turbocharged engine uses lower octane fuel, the sudden increase in cylinder pressure during operation can cause combustion before the spark plug ignites, a phenomenon known as knocking. Under the same pressure, higher octane gasoline remains more stable under high pressure, preventing knocking in the engine. 2. Turbocharged engines generate very high compression ratios during operation. To ensure the engine reaches the ignition moment, higher octane fuel is required. Compared to naturally aspirated engines, turbocharged engines indeed need higher octane gasoline.