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FAQ's & Technical Articles => Techincal Section => Fuel/Oil/Coolant => Topic started by: rsss396 on December 09, 2013, 12:01:58 PM
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Nitro-methane…..everybody knows it's there, but few, it
seems, really know much about it.
http://www.cornwallaeromodellers.ca/PDF_Files/Nitromethane.pdf
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Anyone ever tried to run nitro of and other power adder besides nos?
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A new exhaust system will need to be developed to be able to use nitromethane effectively. Nitromethane has different gas densities and exhaust temperatures.
Nitromethane will require a different timing curve and combustion chamber shape. Nitromethane will require different port timings to work optimally.
In summary: Decide what percentage of nitromethane you are going to use and then develop the whole engine to run that mixture.
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A new exhaust system will need to be developed to be able to use nitromethane effectively. Nitromethane has different gas densities and exhaust temperatures.
Nitromethane will require a different timing curve and combustion chamber shape. Nitromethane will require different port timings to work optimally.
In summary: Decide what percentage of nitromethane you are going to use and then develop the whole engine to run that mixture.
Jerry, I have never ran nitromethane but have wondered if it was better optimized when run slightly lower RPM's, which I believe is much how Nitrous is ran.
So what would happen if you had a methanol motor tuned for max power but on the slightly leaner side of that tune and then added a extra solenoid operated powervalve opening at WOT that would dump 90% nitromethane into the air stream.
This should make the fuel ratio richer but since you can run nitro at 1.3 to 1 this may not be to far out of line.
Air Fuel ratio vs. Resulting Max BTU released
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Nitromethane: o 1.3:1 46,000 BTU
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Methanol: o 5:1 23,000 BTU
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Gasoline: o 12:1 18,400 BTU
obviously I would adjust timing which I believe would be retarded a few degrees, and since only 1 powerjet is dumping nitromethane along with 3 other power jets that dump straight methanol the total amount of nitromethane in the airstream would be much less than the 90% nitro.
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only maybe 10%