Can a Car Designed for 92 Octane Use 98 Octane Fuel?
2 Answers
A car designed for 92 octane can use 98 octane fuel, but it is not recommended. The compression ratios and octane ratings of 92 and 98 octane fuels differ. Using 98 octane fuel in a 92 octane car may increase engine knocking and, in severe cases, cause engine wear. Effects of using 98 octane fuel in a 92 octane car: Engine knocking and wear. 98 octane fuel has the highest octane rating currently available in China. Although it offers better anti-knock performance and higher driving force, cars designed for lower octane fuels should not blindly use higher octane gasoline. Higher octane fuels are more suitable for engines with higher compression ratios, while 92 octane cars have lower compression ratios. Using 98 octane fuel may increase engine knocking and, in severe cases, cause engine wear. Differences between 92 and 98 octane fuels: Compression ratios and octane ratings vary. The compression ratio of 92 octane fuel ranges between 8.5 and 9.5, while that of 98 octane fuel exceeds 9.8. The octane rating of 92 octane fuel is lower than that of 98 octane fuel—92 octane fuel has an octane rating of 92%, whereas 98 octane fuel has an octane rating of 98%.
As a long-time car owner with years of driving experience, I've personally tried filling my 92-octane car with 98-octane gasoline a few times. There were absolutely no issues—the engine ran just as smoothly, and startup was normal. Modern car computer systems are quite intelligent; they automatically adjust ignition timing to accommodate higher-octane fuel, so there's no need to worry about engine damage. But honestly, doing this long-term is a bit of a waste of money. 98-octane fuel costs 2-3 yuan more per liter, meaning a full tank costs over 100 yuan extra with little noticeable improvement in power or fuel efficiency. Unless you're in a remote area temporarily unable to find 92-octane fuel for emergencies, there's really no need to do this. Sticking to the manual's recommendation of 92-octane saves significant expenses—it's more practical to spend that money on tire maintenance or oil changes.
