Can I mix half 92 and half 98?
4 Answers
92 and 98 cannot be mixed. Hazards of mixing gasoline: If the vehicle model specifies high-octane gasoline, long-term use of low-octane gasoline is not allowed, as it will increase the frequency of knocking and aggravate engine wear. Gasoline octane ratings: Gasoline has a high octane number (anti-knock combustion performance) and is divided into grades such as 89, 90, 92, 93, 95, 97, and 98 based on the octane number. Starting from January 2012, gasoline grades 90, 93, and 97 were revised to 89, 92, and 95.
As a young guy who often goes for drives, I've tried mixing half a tank of 92 with half a tank of 98 before, and it actually works fine. The mixture ends up around 95 octane, which most engines can handle. For example, my friend's old car didn't show any issues when he occasionally did this. However, I don't recommend doing it long-term. Why? Because mixing fuels might make the engine less stable. If your car is designed for higher-octane fuel, like some turbocharged models, you might experience slight knocking or black smoke from the exhaust, affecting power and smoothness. Plus, it's completely unnecessary—just filling up with 95 octane directly is much simpler and saves you the hassle of experimenting. Think about it: octane rating is an indicator of gasoline's anti-knock performance, and manufacturers have set recommended values for a reason. Ignoring them could shorten your engine's lifespan. If you're unsure, check the manual or just stick with 95 octane to be safe.
As a veteran driver with decades of experience, I've seen too many people trying to save money by mixing fuels—blending 92 and 98 octane in half actually works out to roughly 95 octane technically, and it won't immediately damage a regular engine. But honestly, it's too risky. Engine designs have specific pressure tolerance requirements, and mixed fuels can cause erratic temperature fluctuations, leading to piston wear over time. The repair costs would far outweigh the savings on fuel. I recall a neighbor who did this long-term and ended up with recurring ignition system issues. My advice is to stick with pure gasoline—use either 92 or 98 octane as specified in your car's manual for peace of mind. Higher octane is better for high-performance cars to prevent knocking, while lower octane saves fuel. Mixing just compromises both safety and performance.
From a technical perspective, mixing half 92 and half 98 octane fuel is feasible, as the average octane rating would be around 95. Most modern vehicles can adapt to this without major issues. However, be cautious about potential knocking caused by the octane difference, especially in high-performance engines that normally use 98 octane suddenly mixing with lower-grade fuel. A one-time mix has minimal impact, but for vehicles with direct injection systems, long-term mixing may cause uneven fuel distribution and increase carbon deposits. The safest approach is to use 95 octane or follow the manufacturer's recommendation, as octane rating directly relates to compression ratio - stability is best.
