What is the best petrol for your car?

Choosing the right fuel for your car is important for your car’s performance and your budget. But how do you know which one suits your car best?

In this article, we break down the differences between fuel types so you can find out which one is best for your car. 

Understanding octanes and fuel 

Ever filled up at a petrol station and wondered what those unleaded numbers at the fuel pumps meant? Those numbers refer to the octane levels in fuels. An unleaded 91 has 91 octanes, an unleaded 95 has 95 octanes, and an unleaded 98 has 98 octanes.  

The Research Octane Number (RON) or octane is a measurement of how much resistance fuel has to ignite your engine. A fuel that burns too quickly in the engine can cause pinging, which may damage your car. 

Higher octane fuels burn slower compared to lower octane fuels that burn quicker when pressurised. This is why high-performance cars, SUVs, and sports cars will run better on higher octane fuel. Regular cars though can run on lower octane regular unleaded fuels just fine. 

What’s the difference between unleaded 91, 95, and 98? 

Now, let’s dig a little deeper and compare the unleaded 91, 95, and 98. 

Unleaded 91 

Also known as Standard Unleaded, this is the most common fuel type in the country. Most cars can use and run on unleaded 91 without any problems. As of writing, prices for this fuel type goes from $1.68 to $2.14 per litre depending on the State or Territory according to FuelPrice Australia. 

If your car doesn’t have high-performance requirements, using unleaded 91 likely won’t cause your car any issues. And being one of the cheaper options out there is certainly a nice plus. 

Unleaded 95

Unleaded 95 or Premium Unleaded 95 petrol is, as the name suggests, a more premium type of unleaded fuel. This fuel type ranges from $1.87 to $2.15 per litre, a bit more expensive than the unleaded 91 but it makes up for it for being more fuel efficient and being better for your engine. 

This is primarily used by more high-performance cars, but it can also be used by most vehicles on the road. The main difference between unleaded 91 and 95 is that the premium unleaded fuel can resist pinging longer which is better for the engine.  

Now, whether or not this is better for your car compared to the unleaded 91 will depend on your vehicle. 

Unleaded 98

It is also called Ultra Premium unleaded petrol, unleaded 98 is the highest-octane fuel available. It gives drivers higher performance and engine operation. Plus, it offers less pollution compared to the lower octane fuel types.  

Because of this Ultra Premium unleaded petrol’s high performance and octane rating, it’s the most expensive fuel at the pumps. The price starts at around $1.90 to $2.16. This fuel type is best used for high performance vehicles like sports cars or vehicles with highly-tuned engines. Some models may only take unleaded 98, too. 

What is E10 fuel?

E10 fuel is a fuel blend that consists of 90% unleaded petrol and 10% ethanol, which is also where the fuel gets its name from. Ethanol is considered a renewable fuel resource produced by agricultural sources, and is less energy dense than oil. Its 94-octane rating is slightly better than the cheapest unleaded option. 

In some cases, depending on where you live, E10 fuel could be the cheapest option at the petrol station. The price for this fuel type ranges from $1.66 to $1.79 per litres. 

Even though it’s cheaper and has a better octane rating than the Standard Unleaded, it isn’t as fuel efficient. Your car’s fuel consumption may increase around 3% with E10 compared to unleaded depending on the design of your car. 

Can my car use E10 fuel?

Or the more pressing question: Is E10 bad for your car? The answer to both those questions is— it depends. 

Usually, cars that take unleaded 91 can also fuel up with E10 without any problems. The slight difference in octane won’t have negative impacts on your car if you decide to make the switch. Cost-wise they’re the same, as well, because what the E10 lacks in fuel efficiency is made up for by being a lot cheaper per litre. 

However, and this is important, older cars (vehicles manufactured before 2005) that take unleaded 91 are not designed to take any ethanol fuels. Cars that aren’t designed with ethanol-based fuels may get damaged while using E10 which means hefty repair bills or worse, a catastrophic failure of the fuel system. 

To know if a fuel type is compatible with your car, it’s best to seek the manufacturer’s advice. It’s always better to be safe than sorry. 

What is the best for fuel economy? 

Higher octane fuels can improve performance and fuel efficiency, but they’re also more expensive. Any improvements may be quite small depending on the make and model of the car, and how you use it. 

Usually, the difference in fuel efficiency is 1% per octane rating. The Standard Unleaded 91 and the Ultra Premium unleaded 98, for instance, has a 7% difference in fuel efficiency. Depending on the price difference though, switching to a higher octane fuel may have little to no impact on your budget. 

A good way to find out which fuel is the best for your car is by trying out different fuels and figuring out which one is most efficient. Fuel up and see how many kilometres you travel or however you need to refuel on a certain fuel type, then rinse and repeat with the others for comparison. 

Before you start switching up your fuel, make sure your engine is up to it by checking beforehand. You can look it up on the owner’s manual, check the fuel cap, or ask your local mechanic. Engines are designed for a minimum octane rating, so take a look at that first before anything else. 

Aside from fuel, there are other ways you can be more fuel efficient like walking more, using a green car or driving an electric car. 

In the market for a more fuel-efficient car?  

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