Should the first tank of fuel for a new car be filled with 95 octane?
2 Answers
If it is a turbocharged engine, it is recommended to use 95 octane gasoline, while a naturally aspirated engine can use 92 octane gasoline. From the perspective of car labeling: The octane rating of gasoline allowed to be filled as indicated by the car is the minimum rating for safe combustion. For example, if it is recommended to fill with gasoline above 92 octane, it means that the minimum octane rating allowed is 92, but the minimum octane rating is by no means the gasoline with the best fuel efficiency ratio. From the perspective of cylinder compression ratio: The preferred choice for filling gasoline is generally based on the cylinder compression ratio. Generally, if the compression ratio is greater than or equal to 10:1, it is recommended to use gasoline with an octane rating above 95. In addition, when the engine is developed, there is a designed gasoline octane rating, and all designs are based on this octane rating. A 10:1 compression ratio engine is generally developed using 95 octane. At this octane rating, the most optimized combustion efficiency can be achieved.
From a technical perspective, the fuel choice for a car engine entirely depends on the manufacturer's recommendations. There's no need to specifically use 95-octane gasoline for the first tank of fuel in a new car. High-octane fuel with a 95 octane rating is primarily designed for high-compression engines or performance vehicles. If your vehicle is a standard sedan or SUV, the owner's manual typically recommends using 92-octane or similar regular gasoline. Modern engines are pre-conditioned during manufacturing, and using higher-octane fuel won't enhance performance or prolong the engine's lifespan—it may just be a waste of money. The key is to read the vehicle's manual and check the recommended octane level. If high-octane fuel is used incorrectly, the engine's combustion process might slightly lose efficiency due to mismatch, but this rarely causes substantial harm to a new car. In short, the first tank of fuel should strictly follow the manual's guidance—don't be misled by marketing gimmicks. This impacts long-term driving economy and stability.
