Everyone knows what a RON number is until someone actually asks what it is? And what does it actually do? The typical answer that someone might give is, the higher the RON number, the more power you get from your car. Technically that is correct but there's a lot more to it than just that!
RON is an abbreviation of Research Octane Number, not RON your next-door neighbour. The research bit is important in RON as that is the difference between your car running efficiently or inefficiently. Unleaded fuel carry RON numbers to help identify the petrol's resistance to detonation.
If you run with low octane fuel in your car and you hear weird rattling or pinging noises, it means that the fuel is detonating instead of burning away smoothly. Not only does this mean you are wasting energy, but you are also damaging the engine. A combustion engine loves to burn fuel. It doesn't, however, love the detonation bit, which is why the correct octane is vital for the engine.
Fuel with a higher octane number can be used to help eliminate knocking. Much older cars that were previously designed to run on a lower RON can also run on fuel with a higher RON number, and in some cases this might actually help the engine. The older the car and the higher the kilometre, the greater the propensity for the engine to knock. This is mainly caused by a build-up of contaminants and carbon deposits which, when hot, can cause pre-ignition-detonation, not burning.
So, the one million dollar question is, does a higher RON give you more power? While it might actually help with fuel economy, unfortunately, if the engine is not designed to take initiative of the higher RON fuel, then it's pretty much useless to your engine and you're instead burning a hole in your pocket. Yes, perhaps the cleaning properties of the higher RON fuel might help your engine work a bit better, but most of it is just waste. It's a bit like fishing with dynamite, it's over-kill!
If you have however tuned your car, and the tuner decided that the engine should run with a higher RON fuel, then yes you must use it, but for most of the everyday cars out there, save your money and just fill up your vehicle with RON 95. That is unless your manual states that you should be using RON97 or higher. When in doubt, refer to the manual.