Octane Number - far0n
Is it me or was unleaded petrol once 95 octane and super unleaded 98 ?? I've noticed that both appear to have dropped down to 94 and 97. Any reason for this ?
Octane Number - BB
Never seen 94. You can get a choice of superunleaded 97, 98, 99 depending on where you go.
Octane Number - Stuartli
I've been using Tesco's 99RON super unleaded in my 1.6 VW Bora - it runs much better and smoother than on the standard stuff and is also supposed to have at least twice the engine cleaning additives of V-Power etc.
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Octane Number - Ruperts Trooper
The relevant standard for unleaded is 95 octane minimum, anything less wouldn't be permitted in the UK.

Super Unleaded is a marketing term so the octane can be anything (but not less than 95).
Octane Number - Saltrampen
I am constantly bewildered by term "engine cleaning power" used by Petrol suppliers..
Many years ago detergents became a standard additive to all petrols, then we had low sulphur fuels
now Higher octane grades with even more cleaning power....
Obviously if you keep adding increased amounts cleaning additives to petrol I guess it may start to affect catalyst operation and combustion efficiency. So I assume that they have changed the type of additive to a more effective one rather than increase the overall additive level too much.
Does anyone know where you can find an unbiased assessment of all the fuels available at the moment
and how well they clean the different types of engine? (ie Direct injection, injection, Turbo etc)...


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