Should the Baojun 730 use 92 or 95 octane gasoline?

[DeBriella]

The Baojun 730 can use 92 octane gasoline. This octane rating is recommended in the vehicle's official user manual. In addition to checking the appropriate gasoline grade in the user manual, the recommended octane rating is also indicated on the fuel tank cap. Generally, the required 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. If the compression ratio is even higher, 98 octane gasoline is recommended. However, with the application of new technologies, the compression ratio alone cannot determine the required gasoline grade, as high-compression engines can also be tuned to use lower-octane fuel. Other factors, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, higher-octane gasoline has a higher octane rating and better 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 the Baojun 730 occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the tank is empty. However, prolonged use of the wrong gasoline grade can have the following effects: For vehicles designed for lower-octane fuel, using higher-octane gasoline will not cause damage, but the increased octane rating may alter the fuel's ignition point, leading to delayed combustion. This reduces the engine's power output and thermal efficiency, resulting in poorer performance. For vehicles designed for higher-octane fuel, using lower-octane gasoline can cause engine knocking. Due to the significantly lower octane rating, the fuel may ignite prematurely during the compression stroke, creating resistance before the spark plug fires. This resistance can make the engine run very unevenly. Mild knocking may only increase noise without noticeable engine damage, but severe knocking indicates serious engine issues, affecting driving stability and causing abnormal wear to pistons and cylinders, potentially leading to cylinder scoring.