Your answers are right here in your chart. Look at the energy content of gasoline versus methanol. Then look at the Stoichiometric fuel/air ratios. It takes much more of the lower energy content fuels to run the engine, and
that is where the extra energy comes from; not the fuel itself. In the case of nitromethane is not so simple, but similar. Nitromethane "carries it's own oxygen", which adds to the power as well.
AV8TOR
Originally Posted by
rglgatortail
Well you seem to miss several ingredients of glow fuel, Methanol is not the power source of glow fuel but is the reason of the catalytic reaction for the glow plug to work, no the power of glow engine comes from the Nitromethane that is added to the methanol to increase power and to make the engine easier to tune so glow fuel has in rights more BTU I cant find the exact number but if you was to take a gas engine say how about a Zenoah 38 cc engine turning a 20 inch prop and make it run on gas and record its high rpm numbers, now take the same engine and make the few mods to the carburetor that it will need and then install a glow plug in place of the spark plug and record the high rpm numbers again you will find that the same engine will in fact turn almost 3000 rpm faster with the same prop because the nitro and methanol in glow fuel. I have done this exact mod to this exact engine to get more power because you just wont get power from a gas engine as compared to a equal size glow engine and that's a fact. Its too bad that Clarence Lee don't visit this forum because he is the guru of model engines and facts of all of this, I do however am relying on old information that I use to read from the now defunct magazine RC modeler magazine. A lot of what I know and what I learned is from what and when Clarence wrote in his articles and im trying to recall what Clarence wrote so im not in total fault here just my memory is not all that what it use to be.
[TABLE]
[TR]
[TD]
Fuel[/TD]
[TD]
Engine Air Flow (cfm)[/TD]
[TD]
lbs of air (lbs)[/TD]
[TD]
A/F Ratio[/TD]
[TD]
Pounds of Fuel (lbs)[/TD]
[TD]
Energy Content of Fuel (BTU/lb)[/TD]
[TD]
Total Thermal Energy (BTU)[/TD]
[/TR]
[TR]
[TD]
Gasoline[/TD]
[TD]
567.53[/TD]
[TD]
42.64[/TD]
[TD]
12.8:1[/TD]
[TD]
2.89[/TD]
[TD]
18,500[/TD]
[TD]
53,176[/TD]
[/TR]
[TR]
[TD]
Methanol[/TD]
[TD]
567.53[/TD]
[TD]
42.64[/TD]
[TD]
6.0:1[/TD]
[TD]
7.11[/TD]
[TD]
9,500[/TD]
[TD]
67,545[/TD]
[/TR]
[TR]
[TD]
Nitromethane[/TD]
[TD]
567.53[/TD]
[TD]
42.64[/TD]
[TD]
1.7:1[/TD]
[TD]
25.08[/TD]
[TD]
5,000[/TD]
[TD]
125,412[/TD]
[/TR]
[/TABLE]
http://www.klotznitromethane.com/