When you arrive at a service station to refuel, you will often find two options: 95-octane and 98-octane petrol. Although both are designed for petrol engines, not every vehicle requires the same type of fuel.
Many drivers assume that 98-octane petrol is always better because it costs more. However, choosing the right fuel depends primarily on your engine’s characteristics and the vehicle manufacturer’s recommendations.
Understanding the differences can help you make an informed decision, avoid unnecessary expenses and keep your engine running efficiently.
What is the difference between 95 and 98 petrol?
The main difference lies in the octane rating, which measures a fuel’s resistance to premature detonation under pressure inside the engine.
95-octane petrol has a Research Octane Number (RON) of 95, while 98-octane petrol has a rating of 98. The higher the number, the greater the fuel’s resistance to uncontrolled combustion.
This characteristic is particularly important in engines operating under high pressure, such as certain sports cars and high-performance vehicles.
For further information about different fuel grades, you can read this RAC guide to petrol and fuel types.
When should you choose 95-octane petrol?
95-octane petrol is suitable for a large proportion of petrol-powered vehicles on today’s roads. If your manufacturer specifies a minimum requirement of 95 RON, this fuel meets the engine’s needs.
Using 98-octane petrol in an engine designed for 95 will not usually provide noticeable improvements in power or fuel economy.
As a result, paying more for higher-octane fuel does not automatically mean better performance.
Which cars need 98-octane petrol?
98-octane petrol is particularly suitable for certain high-performance engines that require greater resistance to premature detonation.
Some sports cars and engines with high compression ratios can benefit from this fuel because it allows them to achieve the performance intended by the manufacturer.
However, it is important to distinguish between recommended and required fuel grades.
If the manufacturer specifically requires 98-octane petrol, using a lower grade may negatively affect engine performance and could potentially cause mechanical problems.
Does 98-octane petrol reduce fuel consumption?
Not necessarily. A higher octane rating does not mean that petrol contains more energy or automatically allows your car to travel further on each litre.
Engines designed to take advantage of 98-octane fuel may experience improvements in performance or efficiency. However, these benefits are generally negligible or nonexistent in vehicles designed for 95-octane petrol.
It is also important not to confuse octane ratings with E5 and E10 fuel labels. These indicate the maximum ethanol content of petrol, rather than its octane rating. Vehicle compatibility with ethanol blends should always be checked.
How can you find out which petrol your car needs?
The easiest way to identify the correct fuel is to check your owner’s manual or the information printed inside the fuel filler flap.
You should find the minimum or recommended octane rating for your engine. Following these guidelines is essential for maintaining proper performance and avoiding unnecessary fuel expenses.
Find the right fuel at ALAS Service Stations
At ALAS Service Stations, we are committed to providing quality fuels and convenient services tailored to different drivers’ needs.
Explore our fuel and vehicle services and check the available fuel prices across our network.
Choosing the correct fuel is another simple way to take care of your vehicle and enjoy every journey.