Thread: Ethanol free fuels?

Higher octane rating from including ethanol can improve the power output - but only if the engine can take advantage of the higher rating. This will not often be the case. For example, if talking about an older engine, you need to increase the compression ratio and tune it for the higher octane (including changing jets), although a modern turbocharged engine may be able to do this under control of the ecu.

Even in these cases, I doubt if the extra power from improved efficiency can make up for the lower energy content of the ethanol.

John

Originally Posted by Blknight.aus

volume per volume, you just broke physics.

mass per mass, probably.

I don't think so Dave, while the energy content of the fuel per unit volume is less for ethanol, you have to bear in mind that only around 25% of that is converted to useful power anyway, so there is plenty of scope for compensating for this by increasing the efficiency of the engine, something that is possible in theory with the raised octane rating.

However, as I pointed out, in practice, this will only actually happen if you actually take advantage of the higher octane, which simply will not happen in most real life situations.

John