Should a Land Rover use 92 or 95 octane gasoline?
1 Answers
Land Rover can use 95 octane gasoline. This fuel grade is recommended in the vehicle's official owner's manual. In addition to checking the appropriate fuel grade in the owner's manual, Land Rover vehicles also indicate the recommended fuel grade on the fuel tank cap. Typically, the fuel grade can also be determined based on the engine's compression ratio. Vehicles with a 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 higher, 98 octane gasoline is recommended. However, with the use of some new technologies, the fuel grade cannot be determined solely based on the compression ratio. High compression ratio engines can also be tuned to use lower octane fuel because factors other than the compression ratio, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, the higher the fuel octane number, the higher the octane rating 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 a Land Rover occasionally uses the wrong fuel grade, simply switch back to the correct grade after the current tank is used up. However, prolonged use of the wrong fuel grade can have the following effects: For vehicles that recommend a lower octane fuel, using a higher octane fuel will not cause damage, but the increase in octane rating can change 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 that recommend a higher octane fuel, using a lower octane fuel can cause engine knocking. Because the octane rating is too low, the fuel's ignition point decreases and it may ignite prematurely during the compression stroke. If the fuel ignites before the spark plug fires during the compression stroke, resistance will occur during the upward stroke. This resistance makes the engine run very unstable. If the knocking is mild, it may only increase noise without significant damage to the engine. However, if the knocking is severe, it indicates serious engine conditions. The vibrations not only affect driving stability but can also cause abnormal wear on the pistons and cylinders, and in severe cases, even cylinder scoring.
