Bio-ethanol

[orch]

I am thinking of converting a Honda Blackbird engined race car to run on Bio-ethanol as I've heard that reasonable power increases can be attained without mechanical changes. Has anyone got any views / advice? in particular what CO figures should be achieved or is there an alternative to use when setting the fueling levels with this fuel?

 

[patprimmer]

With no engine modifications you will only get a very slight power gain.

You will need some modifications to the fuel system to handle the different chemical nature and to handle the extra fuel flow requirements.

Increased compression ratio, like over 13:1 and as high as 16:1 is often required to get the most out of ethanol. It may require different spark timing.

Regards

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[IceStationZebra]

Pat - you touched on the fuel flow requirements. Don't you need something like 25% more volume to get the same energy? This means that you need to carry this extra weight to get the same range or live with a shorter range.

Also, I don't know why Bio-ethanol would be any different than "regular" ethanol. Just a different source. (except maybe the impurities)

ISZ

 

[patprimmer]

Yes.

You need a bigger tank and carry more weight as a result.

I deliberately left the bio comment alone as it was obviously pointless.

Regards

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[Snork]

I've long been a supporter of non-organic ethanol. It seems to that like that is our best chance for energy independence.

 

[swall]

In the U.S., there is no way that ethanol gets you to energy independence.

 

[GregLocock]

The main source of feedstock for industrial production of ethanol is (say it quietly) oil. Therefore displacing gasoline by non-bio ethanol will result in a net increase of carbon emissions, and oil use, most likely.

The jury seems to be out as to whether bio-ethanol from crops is a net positive for carbon emissions or oil use. Obviously the processes that turn organic waste into ethanol are off to a better start, but again, you have to be /very/ careful that you aren't wasting more enrgy than you are gaining.

As an example, when you press straw into briquettes to burn domestically, the processing uses about 16% of the energy content of the straw. That would be OK, except you are using diesel or electricity typically, to create the equivalent of firewood. Energetically it would be much better to close the chimney off and switch an electric heater on.



Cheers

Greg Locock

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[patprimmer]

The reasons I left it alone are:-

The engine has no political or environmental conscience and will not know nor care where or how the ethanol was produced.

This thread could very easily get sidetracked into an environmental rather than an engine technology debate.

I will now pull my tin hat down tight and cover my ears.

Regards

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[z1rider]

As for the extra weight associated with this change, are you referring to the fuel tank weight alone? The (ethanol) fuel itself weighs less per volume unit measure, yet if memory serves, ethanol has a higher energy content per weight unit measure.

 

[GregLocock]

No, lower. A lot lower.

Cheers

Greg Locock

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[patprimmer]

Greg

I presume you are talking about the ethanol. My hat is already pulled down well past the groin.

Regards

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[orch]

Fuel quantity is not a great issue as we run sprint races off road that typically run max 8 laps of a 1/4 mile oval. Power is far more important!

In the UK we have had reports of some cars (ie Lotus elise converted to run on bio ethanol (which is now available as a pump fuel and thus can be used within my class regs)and these have been producing more power than standard. It may just be the cars engine maps are not as conservative original to push the "benifits" of ethanol for everyday use. But if there is a gain to be had.......!

My query really is - if I set my engine up on a rolling road (injected and on programable mapping) what emission figures do I need to aim for to show fueling is correct?

 

[patprimmer]

The same as petrol. The level of hydrocarbons is a measure of rich or lean. It is not effected by what is stoich, but how the a:f is relative to stoich.

Regards

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