Is premium fuel actually worth the extra over supermarket fuel?

In a national newspaper recently they made a statement saying that branded petrol is no better than fuel bought at supermarkets. I know that you are an advocate of good grade fuel and as such, I have been running my now four-year-old Skoda on premium fuel. The paper goes on to say that unless you have a high-performance brand new engine the grade of fuel is not going to make much difference. If that is true, I have been wasting a lot of money buying higher-grade fuel for 20,000 miles and more as it was used in my previous car. What's your opinion?

Asked on 11 July 2019 by robert adams

Answered by Honest John
Misleading dross. For a long time now car manufacturers have been forced to use Super to get the best possible performance out of their engines for emissions tests and I can tell you for a fact that all current engines are optimised for the best fuels for this reason. Higher RON petrol and higher Cetane diesel provide more torque at low rpm allowing for earlier upshifts (even with automatic transmissions) so that alone slightly improves economy. It's also true that the engines produce around 10% more horsepower at higher revs that most drivers never even get to. Branded Super also contains packages of additives to lubricate fuel systems and helps keep the valves (especially in DI engines) clear of carbon build up.
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