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Is there any significance to using alcohol injection over water injection?

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Old 07-29-2003, 07:23 AM
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LCP
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Default Is there any significance to using alcohol injection over water injection?

My main area of concern would be that a rich mixture of water misted into the combustion chamber may not combust as well as a rich mixture of alcohol. Any validity to that theory?
Old 07-29-2003, 07:43 AM
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Default i always use a mixture of methonal and windshield fluid

i try to eye it about 40alc/60windshield fluid - somewher ein there anyway - i think 100 percent alcohol isn't so good but i've noticed way better temp drops using the alcohol mix then when i tried just windshield fluid or just water

i ordered five 5 gallon drums of methanol from a chem company and they've lasted me a while thus far
Old 07-29-2003, 07:50 AM
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Default I'm not looking for lower temps but better combustion...

...since I'm running too large of a jet and getting too much water, I'm running if things would run better with alcohol instead of water.
Old 07-29-2003, 08:43 AM
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Default No actual water injection experience, but here's my $0.02 worth of combustion theory:

While water does not itself combust, the alcohol will. While methanol has a lower boiling point, and lower heat capacity (takes less energy to vaporize one gram of methanol vs. one gram of water, and is less dense - all these facts are versus water - it would likely mess up the combustion much more than water.

If you are running too much water, you are likely disrupting the stoichiometric ratio of fuel and air. Or, you are adding too many water droplets and this disrupts the flame front in the cylinder. With methanol or other alcohol (combustible), you will truly run too rich and this will mess up the engine computer. While methanol is high octane (I think it is something like 104 RON), I'm pretty sure it burns hotter than gasoline. Also any unburnt methanol will get oxidized in the catalytic converter and would likely overheat the catalyst; causing damage to the converter itself - possibly blocking exhaust gas flow.

Bottom line is that I'm estimating your problems would only compound if you switched from water to MeOH (methanol) - but this is just my theory. Hope you find a realtively easy answer to your situation!
Old 07-29-2003, 09:33 AM
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Default

one would think...i've never had any problems - not sure what jets i have though
Old 07-29-2003, 11:56 AM
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Default Water doesn't really combust at all (more)

It vaporizes into steam in the combustion chamber, removing heat and giving it a nice steam cleaning.

Alcohol / methanol burns, so it can act as extra fuel (and at 114 octane, methanol is the sh*t!).

So mixture like K04Madness uses is solid, as is standard over-the-counter-blue (ONLY) washer fluid, which is usally 50/50 water and methanol mix.

It also boils down to are you maxing out your stock injectors? Running lean? Then you can use the exta fuel in alcohol or washer fluid, but it's not as good at removing heat as pure water. If no lean issues, then use all water to remove max heat. Or vary the ratio.

If cylinder temps get too high, then ECU dumps raw fuel to cool combustion chamber. So water will also help with mileage as it avoids the fuel dump by lowering cylinder temps.

But sometimes hard to tell as to get benefits of water, you are running high boost, so mileage sucks to begin with.

Bruce
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