Should Haval Use 92 or 95 Octane Gasoline?
2 Answers
According to the official vehicle manual recommendation, Haval should use 92 octane gasoline. In addition to checking the suitable gasoline grade in the vehicle manual, Haval owners can also find this information on the fuel tank cap, which is typically labeled. Generally, the gasoline grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should use 92 octane gasoline, while those with a compression ratio between 10.0-11.5 should use 95 octane gasoline. However, with the application of new technologies, the gasoline grade cannot be solely determined by the compression ratio. High compression ratio engines can also be tuned to use lower octane gasoline because, besides the compression ratio, other factors such as ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally, the higher the gasoline octane number, the higher the octane value and the better the anti-knock performance. 92 octane gasoline contains 92% isooctane and 8% n-heptane, while 95 octane gasoline contains 95% isooctane and 5% n-heptane. If Haval occasionally uses the wrong gasoline grade, simply switch back to the correct grade after consumption. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles recommended to use lower octane gasoline, using higher octane gasoline will not cause damage, but the increase in octane value will alter the fuel's ignition point, leading to delayed combustion in the engine. This means both the engine's power output and thermal efficiency will decrease, resulting in poorer performance. For vehicles recommended to use higher octane gasoline, using lower octane gasoline can cause engine knocking. Because the octane value is too low, the reduced ignition point may cause premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance will arise during the upward stroke. This resistance makes the engine run very unstably. If the knocking is mild, it may only increase noise without significant engine damage. However, noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, and in severe cases, cylinder scoring.
I've driven quite a few Haval models, including the H6 and F7 series, and found that choosing between 92 or 95 octane gasoline depends on engine design. Most Haval models have a compression ratio between 9.5:1 and 10.5:1, and generally, 92 octane is sufficient because it has a lower octane rating but offers better cost performance. If you use 95 octane, it has a higher octane rating, reducing engine knocking and making the ride smoother, but it costs about 5% more. I've driven long distances on highways and compared the two, finding that fuel consumption with 92 octane is basically the same—saving money without sacrificing performance. Of course, the car's manual is the authority, so be sure to check the specifications for your specific model. Using the wrong octane long-term may lead to carbon buildup or piston damage, which isn't worth it, so I stick to the recommended octane and pair it with regular fuel system cleaning to keep the car in better condition.
