Is it okay to use higher-grade gasoline in a low-end car?
3 Answers
It is not recommended to use higher-grade gasoline; just follow the manufacturer's recommendation. The reasons are as follows: 1. Explanation of gasoline grades: The octane number of gasoline represents its anti-knock performance, but higher is not necessarily better. Car owners should choose gasoline with the appropriate octane number based on the engine compression ratio specified in the vehicle's manual. Using gasoline with a lower octane number than recommended can lead to increased cylinder temperature, incomplete combustion, reduced power output, engine knocking, and even damage to the vehicle's ignition system. Conversely, blindly choosing gasoline with an excessively high octane number can alter the ignition timing, cause carbon buildup in the cylinders, and, over time, affect the engine's lifespan. 2. Gasoline grade and compression ratio: The commonly referred-to 90, 93, and 97 octane numbers represent the ratio of the actual gasoline's anti-knock performance to that of standard gasoline. If a high-compression-ratio engine uses low-octane gasoline, it can cause knocking, accelerate component aging, and lead to frequent malfunctions.
I find this question quite interesting because I often research automotive engine knowledge. Simply put, low-end cars using higher-octane gasoline is usually feasible and won't directly damage the vehicle, but it's truly unnecessary to waste money. Engine designs already account for specific compression ratios - those economy cars perform perfectly fine with regular 87-octane fuel. Switching to premium 91 or 93 octane brings no real benefits. High-octane gasoline primarily prevents knocking in high-performance engines, whereas low-end vehicles with lower compression ratios will simply have their engine computers automatically adjust, yielding no performance gains or fuel efficiency improvements. Prolonged use may even lead to carbon buildup affecting combustion efficiency. I recommend checking your owner's manual and using the recommended fuel grade - this saves money while ensuring optimal engine operation. If it's just for psychological comfort, occasional use is fine, but don't make it a habit.
From a cost-saving perspective, using higher-octane gasoline in low-end cars is completely unnecessary. After years of driving, I've found that higher-octane fuel costs an extra one or two yuan per liter, adding up to over ten or twenty yuan for a full tank. Yet, for my old Santana, it makes no difference at all. The engine performs the same—no faster acceleration, no reduced fuel consumption. It's better to save that money for higher-quality engine oil. Low-end car engines are designed simply, and high-octane gasoline may not burn completely, leaving residue that affects long-term performance. I usually advise friends to first check the recommended octane rating on the fuel cap—87 is usually sufficient. If they really want a slight performance boost, regular maintenance like cleaning the throttle body is far more cost-effective. In short, spend money where it counts, not on things that don’t make a difference.