Should the Vellfire use 95 or 92 octane gasoline?
2 Answers
The Vellfire is better suited for 92 octane gasoline and does not require the use of 95 octane. Engine Introduction: Although this vehicle is an import, it is not positioned as a high-end model and is equipped with a 2.5L naturally aspirated engine. Difference Between 95 and 92 Octane Gasoline: The primary difference lies in the octane rating, with no other fundamental distinctions. 95 octane gasoline consists of 5% n-heptane and 95% isooctane, while 92 octane gasoline is composed of 8% n-heptane and 92% isooctane. Higher octane gasoline has greater anti-knock properties, but it also comes at a higher cost. 95 octane gasoline has a higher octane rating than 92, making it more stable and easier to burn, resulting in greater power output compared to 92 octane.
I usually drive an Alphard, relying on it for daily commutes and weekend family outings. I tried using 92-octane gasoline for a few weeks and felt the car was a bit slower to start, with slightly higher fuel consumption—about 0.5 liters more per 100 kilometers. The manufacturer's manual clearly recommends 95-octane gasoline due to the engine's high compression ratio, which ensures more complete combustion and prevents knocking sounds. Using 95-octane long-term is better for engine health. While 92-octane is cheaper, the Alphard is an imported vehicle with a highly precise engine. Saving a bit on fuel might lead to issues like carbon buildup or spark plug failures, which could be costlier to repair. Now, I consistently use 95-octane—it runs smoothly and safely, and I even save on maintenance frequency.
