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Do I need to use high octane fuel in my Porsche?

Can you advise, my Porsche has 98 octane fuel printed on the filler cap. This is not always available and I use 95 Octane without any discernible effect, then filling the tank with 99 octane now and again to give the engine a treat, as it were. Is this as ridiculous as it sounds?

Asked on 5 April 2024 by Howard Rigby

Answered by David Ross
As you own a performance vehicle, you will benefit from maximum performance when using high octane fuel. Because it is a relatively modern vehicle, if it detects lower octane fuel being used it will alter the engine timing to avoid pre-detonation, but as a result you will not be achieving best performance, although you may have not noticed any difference. If you occasionally use higher octane but mostly use lower octane this may not be sufficient for the engine to achieve full performance. If it is affordable, we would recommend using higher octane whenever possible as it will ensure best performance and likely contribute to engine longevity and condition too.
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