Does premium unleaded fuel make any difference?

Is there any benefit to spending more money on premium unleaded fuel?

We decided to find out using Paul Maric’s own Ford Ranger Raptor, and the VinFast Proving Ground in Lang Lang, Victoria.

Before we get into the results it’s worth taking a quick look at what a fuel’s RON, or octane rating, means in practice. In the simplest terms, it’s a measure of the petrol’s resistance to burning.

In Australia, most petrol forecourts offer 91 RON regular unleaded, before stepping up to E10 (94 RON), 95 RON premium unleaded, and 98 RON premium unleaded.

High-performance engines generally have a higher compression ratio, and require fuel with an increased burn resistance.

Putting 91 or 95 RON unleaded in a car designed for 98 RON petrol can lead to engine knock, whereby the petrol burns too early and may damage the engine, or lead to greater wear and tear over the long term.

Using a lower octane fuel can also have an impact on the performance of your car, even if it isn’t doing damage.

To see what impact each type of fuel had on the Raptor – which is rated to run on regular 91 RON or higher– we first put 98 RON premium unleaded (in this case, Ampol Amplify) in the ute and tested its 0-100km/h, 80-120km/h, and quarter mile times.

We then used the high-speed bowl at the proving ground to run the Raptor down to empty, headed back to the petrol station, and fuelled up with 95 RON and repeated the process.

As you can see, there was a marked difference between the three different fuel types.

What sort of fuel do you put in your car?