What is the difference between 92 gasoline and 95 gasoline?
2 Answers
92 gasoline and 95 gasoline differ in their composition and performance. The specific differences are as follows: The composition of 92 and 95 gasoline is different: 92 gasoline consists of approximately 92% isooctane and 8% n-heptane, while 95 gasoline consists of approximately 95% isooctane and 5% n-heptane. Isooctane has better anti-knock properties, whereas n-heptane has poorer anti-knock properties. Therefore, the higher the octane rating, the better the gasoline's anti-knock performance. Each engine is given a comprehensive evaluation before leaving the factory, and based on the engine's performance and other data characteristics, the required anti-knock properties are determined, which dictates the appropriate octane rating of gasoline to be used. The performance of 92 and 95 gasoline is different: 95 gasoline, with its higher octane rating, is suitable for engines with higher compression ratios. This is because, as the engine speed increases, the ignition timing in the cylinder advances. When the speed reaches a critical point, the fuel-air mixture may ignite prematurely before the spark plug fires, a phenomenon known as knocking. Increasing the gasoline's octane rating can effectively enhance its resistance to knocking.
As a driver who frequently takes long-distance trips, I've tried both 92 and 95 octane gasoline. The most fundamental difference lies in anti-knock performance - 95 octane fuel has higher octane rating, making it less prone to premature self-ignition under high engine compression ratios. For example, our old turbocharged car's manual explicitly requires 95 octane. If you accidentally fill it with 92, you'll clearly hear 'knocking' sounds from the engine when climbing hills - that's detonation. However, naturally aspirated engines run perfectly fine on 92 octane. Many people mistakenly believe 95 octane is cleaner or more fuel-efficient, but in reality the cleanliness is identical and any fuel savings are negligible. What fuel to use mainly depends on the label inside your fuel filler cap - blindly using higher octane is essentially donating money to gas stations.
