Compression Ratio 10.3: Should I Use 92 or 95 Octane Gasoline?
2 Answers
For an engine with a compression ratio of 10.3, it is recommended to use 97 octane gasoline. Specific guidelines for selecting gasoline based on a compression ratio of 10.3 are as follows: Choosing gasoline according to compression ratio: - For compression ratios between 7.5～8.0: Use 90 octane gasoline. - For compression ratios between 8.0～8.5: Use 90～93 octane gasoline. - For compression ratios between 8.5～9.5: Use 93～95 octane gasoline. - For compression ratios between 9.5～10: Use 95～97 octane gasoline. How to check the compression ratio: The compression ratio can generally be found in the car's manual. In addition to the manual, car manufacturers often indicate the recommended fuel grade on the inside of the fuel tank cap. Car owners should strictly follow the engine's specific compression ratio to select the corresponding octane gasoline, ensuring the engine performs at its best.
Having been in the automotive field for so many years, I think a compression ratio of 10.3 with 92-octane gasoline is completely fine. This compression ratio isn't high, it's at a medium level, and the anti-knock properties of 92-octane are sufficient. It's both cost-effective and practical. I remember once helping a friend check his car—it had a similar compression ratio around 10-point-something, and he'd been using 92-octane gasoline all along. After over 100,000 kilometers, the engine was still running strong with no knocking issues. The key is to check the owner's manual—what's written there is authoritative. Don't be fooled into spending extra on 95-octane. With normal driving and gentle acceleration, the engine runs very smoothly. Unless you're constantly revving high like in racing, then you might consider upgrading. In short, don't worry unnecessarily—92-octane is economical and suitable for most daily commutes. The money saved on fuel can fund several long trips.
