What are the effects of using different gasoline in cars?
1 Answers
Using gasoline with different octane ratings and from different manufacturers can lead to variations in vehicle performance and may impact engine longevity. Not only does the octane rating affect engine torque, but even gasoline with the same rating from different producers can result in different engine power outputs. More details are as follows: 1. Currently, gasoline on the market comes in various octane ratings such as 90, 93, 95, and 97. These numbers represent the gasoline's octane number, indicating its anti-knock properties, and have no relation to the cleanliness of the gasoline. The notion that "higher octane gasoline is cleaner" is entirely misleading. 2. It is more scientific and economical, and maximizes engine efficiency, to refuel according to the engine's compression ratio or the vehicle's manual specifications. During the design phase, car engines are configured to use a specific gasoline grade based on the compression ratio. 3. The compression ratio is a crucial structural parameter of an engine, defined as the ratio of the volume of gas at the start of compression (when the piston is at bottom dead center) to the volume at the end of compression (when the piston is at top dead center). From the perspectives of power and efficiency, a higher compression ratio is generally better. A high compression ratio enhances power output, thermal efficiency, and consequently improves acceleration and top speed. However, the compression ratio in gasoline engines cannot be too high due to limitations imposed by cylinder material properties and the risk of combustion knock. 4. Simply put, high-compression engines require high-octane fuel. Higher-octane fuel burns more slowly, reducing combustion knock, which is why engines with higher compression ratios need it. Conversely, lower-octane fuel burns faster and produces more combustion knock, making it suitable for engines with lower compression ratios.
