Should the Hongqi H5 use 92 or 95 octane gasoline?

[LeColeman]

Hongqi H5 uses 92 octane fuel, which can be found in the vehicle manual and on the fuel tank filler cap. Although 95 octane gasoline has better anti-knock properties, the difference is not significant for engines that can use 92 octane fuel. The selection of gasoline octane and considerations are as follows: Selection of gasoline octane: Generally, the main basis for selecting gasoline octane is the engine's compression ratio. A compression ratio of 8.0-8.5 should use 90-93 octane gasoline; a compression ratio of 8.5-9.5 should use 93-95 octane gasoline; a compression ratio of 9.5-10 should use 95-97 octane gasoline. Considerations for gasoline octane selection: Generally, if a high-compression-ratio engine uses low-octane gasoline, it can lead to incomplete combustion, strong engine vibration, reduced power output, damage to engine components, increased fuel consumption, and poor driving performance. Conversely, if a low-compression-ratio engine uses high-octane gasoline, it can cause delayed ignition, meaning the fuel does not reach the auto-ignition point at the highest compression ratio, leading to incomplete combustion. This requires additional fuel injection to ensure power output, which not only does not benefit the engine but also increases fuel consumption.