My experience with ethanol fuel.

BaronVonChickenPants · Post by **BaronVonChickenPants** » Mon Feb 27, 2006 9:21 pm

Due to an empty tank and a lack of other options I invouluntarily decided to trail some 98 octane fuel with 10% ethanol. No from a little research I've discovered that, all speculation and bs aside, ethanol has a similar effect to NO2 just on a smaller scale, ie: offers no extra energy to the burn, just assist and improves the burn by adding more oxygen.

So in theory 10% ethanol gives 10% less energy for the same volume, meaning you need to use 10% more fuel to achieve the same energy.

In practice I got very close to 10% less distance out of it (still more than standard unleaded though) but I did get a very noticable increase in performance, both in response and general power.

Does anyone have some actual un-biased info on ethanol, not just it's bad because thats what everyone tells me.

Jordan.

MUDRAT · Post by **MUDRAT** » Mon Feb 27, 2006 10:39 pm

Basically Ethanol (C2H50H) burns (+3O2) and forms two Carbon Dioxide (2CO2) molecules and 3 Water (3H2O) molecules.

The water may then be further oxidised to yeild further Hydrogen and Oxygen to the process or exhausted.

This is a perfectly clean Hydrocarbon Combustion (note lack of CO) - Petrolium does more damage - mostly due to the other hydrocarbons that are added to the petrol - or in secondary reactions attributed to incomplete initial combustion.

BaronVonChickenPants · Post by **BaronVonChickenPants** » Mon Feb 27, 2006 10:50 pm

Thanks muddy, I know on it's own ethanol is awesomely clean fuel, and somewhere down the track I want to make an ethanol or methanol powered generator.

BUT what about inside an engine intended for (un)leaded petrol, and the supposed effects on fuel line rubbers, more than anything are there likely to be any detrimental effects?

What about unforseen benefits?

Cheers,
Jordan.

subanator · Post by **subanator** » Tue Feb 28, 2006 12:19 am

Muddy, does it burn hotter or cooler?
Would plug gaps have to resized or better spark required?
What about "knock" characteristics?

MUDRAT · Post by **MUDRAT** » Tue Feb 28, 2006 3:28 am

Actually as Pure Ethanol has an octane rating of about 106, predetonation is not a factor. That does mean however that energy yeild per unit (this is called Energy Density) will be much lower than gasoline, hence fuel economy will deteriorate.

To quantify:

Energy Density of Gasoline is about 40,000 kJ/m3
Energy Density of Ethanol is less than 20,000 kJ/m3

That's half as much!

Ethanol IS an almost perfect solvent: it has cleaning effect that will remove rust and other junk from the fuel system. This necessitates frequent fuel filter changes until the fuel system is cleaned out.

As there is no rubber used in the fuel system (all the fuel lines are made of Neoprene) which is impervious to degradation by gasoline or other additives. I can't see that it will have any negative effects in that way.

Interesting fact: The Brazilan Army (From South America, NOT the adult show) use Ethanol fuel exclusively for all of their light transports.

BaronVonChickenPants · Post by **BaronVonChickenPants** » Tue Feb 28, 2006 7:18 am

Thanks for that Nathan thats what I wanted to know.

I'm prepared to sacrifice 10ish% distance for the extra performance, it was actually really impressive from just changing fuel, much more signifficant than ULP -> PULP.

Jordan.

fredsub · Post by **fredsub** » Tue Feb 28, 2006 8:29 am

Brazillian economy is 80%ethenol or some such......
efi cars there have some additional sensor to adjust for varying mixtures...
not sure whether it effects ignition or fuel or both?
I bets that advancing ignition would do the most good.

With ethanol you get the 10% less......but do they charge you 10% less too?
I am thinking not!

I think the big debate about ethanol is the amount of energy consumed to produce it....and the greater incentive to produce more yield in the crop by ever greater usage of fertilizer!!

As usual the bloody greens have their heads in the sand when it comes to the cons. for so called greener fuels.

PeeJay · Post by **PeeJay** » Tue Feb 28, 2006 8:56 am

I've got a tank of the same stuff and so far I've done 220kms and noticed no difference. Considering it's $0.13/L less than preimum I know I'm going to be using a whole heap more of it!

MUDRAT · Post by **MUDRAT** » Tue Feb 28, 2006 10:56 am

I'm going to use it as it becomes more available in the country. That is if my favourite servo stocks it (the chicks are hotter there

).

vidler · Post by **vidler** » Tue Feb 28, 2006 8:06 pm

i spose i better crank up my still and make my own fuel addative if there is no bad side 2 it apart from less kms.... have 2 try it anyway

one for you, one for me

one for you, one for me

one for you, one for me

:P :P

subanator · Post by **subanator** » Tue Feb 28, 2006 11:52 pm

My old boss who was a South African, said they use ethanol mix over there also. I remember he said a lot of ignition mods were the go as altitude adj. I thought their fuel was of poor quality from what I believe.

fredsub · Post by **fredsub** » Wed Mar 01, 2006 8:27 am

yeah the fuel is good for the motor.
I just hate it when servos compete on price by 5c or less, but they have ethanol in the fuel...and are not up front about it.

Better they are up front about it, and give us the bloody 10% discount off the ULP price

86rxturbo · Post by **86rxturbo** » Tue Mar 14, 2006 8:42 pm

just wondering if using methanol could be used as a subsitute like ethanol since there from the same process does it make any difference

MUDRAT · Post by **MUDRAT** » Tue Mar 14, 2006 8:56 pm

Yes Methanol can be, however the engergy density is even lower. Methanol is also terribly corrosive to any steel fuel system componants.

PeeJay · Post by **PeeJay** » Tue Mar 14, 2006 9:10 pm

I just emptied my 4th tank of the stuff this week any my fuel ecconomy just keeps getting better! I did a run up Putty Rd to Muswellbrook and back via Newcastle on the weekend, 570kms from 50L. I thought EJ20Gs were supposed to be fuel guzzlers! Every tank I get another 15-20kms from it.

subanator · Post by **subanator** » Wed Mar 15, 2006 12:50 am

MUDRAT wrote:Yes Methanol can be, however the engergy density is even lower. Methanol is also terribly corrosive to any steel fuel system componants.

I have been told that Ethanol can be corrosive too, to steel or alloy I am not sure. Anyone?

MUDRAT · Post by **MUDRAT** » Wed Mar 15, 2006 5:02 am

It's definately corrosive to rubber, but I'm not sure about steel or alloy.

tim_81coupe · Post by **tim_81coupe** » Wed Mar 15, 2006 9:06 am

I thought ethanol was corrosive to steel & alloy because it allows water molecules to bond with the fuel.

mattims · Post by **mattims** » Wed Mar 15, 2006 9:58 am

well i think the idea is you dont put too much water in the fuel. Probably bad for water injection?

MUDRAT · Post by **MUDRAT** » Wed Mar 15, 2006 7:20 pm

It's true that Ethanol will "absorb" water in fuel.

I'm just thinking though that:

a) Once the water has bonded with the Ethanol, why would it dissociate and bond with the steel and then oxidise the steel? Unless the steel had a higher charge/polarity than the ethanol, which I guess can be possible.

b) Subarus use either aluminium alloy (block/heads/manifold) or coated steel (fuel and vapour lines) in their engines?

I'm thinking the fact that water bonds with Ethanol would be a good thing.

Just what I'm thinking mind you, can't back this up eh.