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Hi all , I've been looking into ethan as fuel or fuel petrol blends to see what interesting properties it has .

I have noticed in the past on some American car entheusiast sites that E85 was getting a regular mention and there had to be something in it .
Most people by now would know that the E number represents the percentage of ethanol in a petrol blend ie E10 means 10% ethanol 90% petrol . I think back in the G11 Charade days (pre Ellie RX) I had tried E15 and the result was a bit lame - possibly due to the 85% petrol being garbage . The ripping snarling 3 cyl carby 1000 didn't like it for some reason .

When the price was a bit less horrendous than now days I also tried the 100 octane Shell V Power Racing E5 and it was good though not fantastic probably because neither the Skyline or the RX was tuned (advanced up) enough to get the benefit of its higher octane rating . I think it's off the market now .

E85 sounds really interesting but Ethanol in high percentages (85%) is not something you could probably just dump in a car not tuned to run on it .

From research so far ethanol doesn't develop the same heat per unit volume as petrolium fuels , don't quote me but I think its down around 66% . Obviously then it needs to be used in higher ratios with air than petrol does .

To date I believe the chemically correct ratio of air to fuel (by mass or weight) is 14.7 to 1 , meaning in this ratio you burn all the fuel and all the oxygen in the combustion cycle .
With ethanol alcohol I think the ratio comes down to ~ 9.7 to 1 for the chemically correct burn .

I think we should be able to get away with ethanol blended with petrol in ratios up to possibly E20 and the reason why being that many production (supposedly emissions clean) cars run quite rich under high loads but with pretty retarded timing to lower NO emissions .

Last night I was reading threads at the Holden LS1 Edit site about those cars having mapping suitable for running E85 already but not factory enabled .

They are saying that it's generally the water content in ethanol that can make it corrosive to some metals , I imagine probably like mineral brake fluid is because it's also hydroscopic (absorbs water) .

More as later , cheers A .

i would happily run my car 100% on ethanol, but the problem is that i would require a lot more fuel, as it requires more fuel to make the same boom safely. that and it doesnt make the same boom (less actually), but you get it back with interest by adding timing and more boost (or higher comp ratio).

the thing i hate about E10 (etc) is that they are making it 91ron. that's fine, but the 90% of the petrol in it is cr@p and they are using the 10% ethanol to bring the ron up. this is why 5% ethanol on top of vpower 98 gives them 100ron (it's still around, just only at a few places)

and yes, that's the problem with ethanol. eats away at metal. methanol eats away at rubber.

in europe they regularly use e85