What are the consequences of using 92-octane gasoline in a BMW X6?

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If a BMW X6 uses 92-octane gasoline for an extended period, the following effects may occur: For vehicles recommended to use lower-octane gasoline, using higher-octane fuel will not cause damage. However, the increase in octane rating alters the fuel's ignition point, leading to delayed combustion in the engine. This results in reduced engine power and thermal efficiency, with the actual driving experience being diminished performance. For vehicles recommended to use higher-octane gasoline, using lower-octane fuel can cause engine knocking. Due to the significantly lower octane rating, the fuel's ignition point decreases, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance is created during the upward stroke. This resistance makes the engine run very unevenly. If the knocking is mild, it may only increase noise without obvious engine damage. However, noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, potentially leading to cylinder scoring in extreme cases. According to the official vehicle manual, the BMW X6 is recommended to use 95-octane gasoline. In addition to checking the recommended gasoline grade in the manual, the BMW X6's fuel cap also displays this information. Typically, the appropriate gasoline grade can also be determined by the engine's compression ratio. Vehicles with a compression ratio between 8.6-9.9 should use 92-octane gasoline, while those between 10.0-11.5 should use 95-octane. Higher compression ratios may require 98-octane gasoline. However, with advancements in technology, compression ratio alone is no longer the sole determinant. High-compression engines can be tuned to use lower-octane fuel due to other influencing factors such as ignition timing, turbocharging technology, and Atkinson cycle technology. Generally, higher-octane gasoline has a higher octane rating and better anti-knock properties. For example, 92-octane gasoline contains 92% isooctane and 8% n-heptane, while 95-octane gasoline contains 95% isooctane and 5% n-heptane.