With alchi improve octane?

[saleen281]

If the car's tune ifs left alone and the methonol concentration is above 70%, will the octane totoal actually be increased? Theory being that methanol is like 130 octaneand if added to the bmixture could act as octance additive

[Gruppe-S]

Up to a certain point there are substantial diminishing returns. Keep in mind that the power potential (available energy per mole) of methanol is substantially less than that of high octane gasoline.

In practice this means you will have great difficulty seeing a substantial octane improvement by increasing mixture.

Cheers,

Gary
Gruppe-S

[EVOlutionary]

Originally Posted by saleen281

If the car's tune ifs left alone and the methonol concentration is above 70%, will the octane totoal actually be increased? Theory being that methanol is like 130 octaneand if added to the bmixture could act as octance additive

Here are a few key points:

- If the car's tune is left alone (tuned for pump gas) it will make the most power on the lowest octane of pure gasoline that you can use without detonation.

- Mixing alcohol in any concentration from 0-100% with pump gas will increase the octane rating.

- Neither methanol nor ethanol's octane rating are that high. I believe they are in the 1teens (113-117 or thereabouts. . . )

[saleen281]

sorry thought it was higher... i live in ca the land of 91 and gas prices that will make you have a heart attack

[saleen281]

oh btw.... what gains would u expect on a car with just cams... ball park

[joseph k]

do some searching saleen, this is the second post you have started in the last few hours w/ answers already on the site somewhere. not trying to bust your balls but use the site first, then ask questions that you didn't find the answer to