Unleaded petrol prices are all over the place these days, especially with things going on in the world today. As a result, an age-old question has emerged yet again: what’s the difference between regular and premium unleaded petrol? Will you hurt your engine by using the wrong one?
Premium unleaded petrol fuels are those with higher octane levels than regular ones, i.e., regular petrol typically has an octane/RON level of 91, while premium fuels are RON 95 and above. Premium petrol is necessary for high-performance engines because they’re more stable at higher compression.
There’s plenty of marketing hype and myths surrounding premium unleaded petrol that you’ll want to avoid. So, read this guide to the end to understand what premium petrol is, who needs it, does your vehicle need it, and what happens if you don’t use it.
Let’s get started.
What Is Premium Unleaded Petrol?
The fuel industry defines premium unleaded petrol as any petrol with a RON of 95 and above. Aside from that, premium fuels also contain additives that clean your engine from the inside and maximise its performance.
In Australia, you’ve likely seen several petrol options in that category. Take note that most petrol stations have several premium fuel options like RON 95 unleaded petrol, RON 97, and even RON 98, aside from the standard RON 91 unleaded petrol.
I’m not surprised at all that people get confused, but don’t worry, this post will get you up to speed with all the different RONs you see at the servo.
What Do Higher Octane Levels in Fuel Mean?
RON stands for Research Octane Number, and it represents the fuel's octane levels. A higher octane level (or the RON) means a more stable fuel. That's especially true in high-performance engines that compress the fuel far more than a standard engine would.
In other words, premium unleaded petrol at RON 95 or above is often required for cars with high-performance engines. These engines compress fuel much more than standard ones, so higher-octane fuel is necessary to prevent engine problems, like spontaneous combustion and engine knocking.
However, you must see past the marketing hype surrounding premium petrol. More on that later.
Will It Hurt My Car If I Don't Use Premium Unleaded Petrol?
If your car’s engine is not considered high performance, then it’s perfectly OK to use regular unleaded petrol.
Many fuel companies will hype their premium unleaded petrol by talking about their benefits. While those claims are accurate, it doesn’t mean that your car engine will suffer without premium fuels.
It also doesn’t mean that standard fuels with lower octane levels are bad or that they’ll somehow hurt your engine.
The bottom line is simple: premium unleaded petrol is only necessary if your car’s manufacturer says so in the owner’s manual. If it doesn’t, follow the manufacturer’s fuel recommendations and your engine will function optimally.
What Are the Benefits of Premium Unleaded Petrol?
Generally, premium unleaded petrol means better performance and more efficient engine maintenance.
More specifically, these are the four areas where premium unleaded petrol is more effective than standard fuels:
- Cleaning: Premium fuels come with additives that are highly effective at removing carbon deposits that naturally build up inside the engine as a result of the combustion process.
- Lubricating: Premium unleaded petrol also helps to lubricate the engine and its moving parts, reaching into the inner recesses where other oils and lubricants might be unable to.
- Protecting: Higher-octane fuels also safeguard the engine's most crucial components, particularly the fuel pump and fuel injectors, which are prone to clogging after many years of use.
- Minimising corrosion: Premium fuels minimise corrosion, protecting fuel filters and contributing to the engine’s overall performance.
Myths About Premium Unleaded Petrol
If you think that the list above misses a few benefits that you believed in or heard about, that’s because those supposed benefits are only myths.
Some of the myths surrounding premium unleaded petrol include the following:
- “Premium petrol means more power”: This is untrue. Premium petrol doesn't magically cause your engine to generate more power. At the most, it maximises your engine's capabilities, but you can get the same result with standard petrol.
- “Premium petrol leads to better mileage and performance”: Again, this is untrue. You’ll get the same results with standard petrol as long as it matches your engine’s minimum octane requirements.
- “Non-premium petrol will damage your engine”: No, using standard petrol in a car engine will not cause damage. You can even mix premium and non-premium petrol, and there won't be any damage. Just make sure you don't mix diesel where it doesn't belong!
I've mentioned this before, but it's worth repeating: your car engine will do precisely what it's designed to do when you meet its minimum octane fuel requirements.
If your engine requires premium fuel, then by all means, use premium unleaded petrol. But if it doesn’t, you’re not hurting it by sticking with standard fuel options like unleaded petrol 91 RON.
Is 91 or 95 Unleaded Petrol Better?
RON 95 premium unleaded petrol is better than RON 91 in the sense that it's more stable at higher compression and contains additional additives.
However, that also means that it costs more than RON 91 fuel. Also as mentioned above, if your car requires 91 RON, then using 95 RON does not make it any better than what it’s capable of doing.
The additional benefits for someone driving a standard car are negligible, making it not worth paying the heftier price tag for that fuel.
So, again, stick to the fuel type your car's manufacturer recommends, and you'll be better off. Your vehicle will perform as it should, and your wallet won't be unnecessarily hurt.
What Kind of Fuel Does My Car Need?
You can find out the fuel your car needs by referring to the owner’s manual. The manufacturer places their recommendations in the manual to let you know the minimum octane level required by your engine.
High-performance engines require premium unleaded petrol as their bare minimum. However, most cars on the road function perfectly fine using standard RON 91 petrol.
Sure, you can invest a little more in buying higher-octane fuel. However, remember that after a certain price point, the potential benefits are no longer worth the price you pay for premium unleaded petrol.
Hope that clears up the confusion and you’ll have no more hesitations next time you’re pumping the bowser.
Check out the CarpartAU Blog to learn more about everything to do with cars. You’ll find plenty of informative articles that help you understand topics like fuel, maintenance, repairs, spare parts and more!
By Ray Hasbollah