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Old 22-12-2004, 04:39 AM
hotrod hotrod is offline
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Join Date: Oct 2003
Posts: 307
Default Nitro

Nitromethane by itself has limited water solubility.
2.2 cc H2O / 100 cc nitromethane. Listed as soluable in both water and methanol. I suspect mixed with methanol that limit is pretty much not an issue as the methanol is 100% miscible in water.

autoignition temp 785 deg F ( 418 deg C ), lower explosion limit in air 7.3%, used in rocket fuels and some explosive mixtures. Most RC fuel is a mixture of nitromethane and methanol at 5% - 15% nitro plus a lubricant like castor oil or a synthetic castor oil. Its been a long time since I bought any, not sure if you can buy it over the counter without the lubricant as most RC models use the fuel for cylinder lubrication. It's hard to find and expensive in pure fuel grade form, usually only sold through racing fuel outlets.

Nitro's main advantage is that it only needs about 1/10 th the oxygen to burn that gasoline does, so you can burn a huge amount of it as fuel for a given amount of free oxygen in the cylinder. AA fuelers pump so much fuel that its like shooting a garden hose into each cylinder.

In high purity concentrations it is explosive from shock, which along with efforts to control top speeds NHRA currently limits it to a maximum concentration of about 85%. Years ago they had some nasty engine explosions with higher concentrations. Like Nitrous oxide systems, if you go lean it will cook an engine before you can lift your foot off the throttle. Because of this I don't think it would be a really good idea to use a water/nitromethane injection system except in a fully mapped injection setup like the top end Aquamist systems. A fixed rate injection would likely go lean at high rpm if your using it in any significant amount. As one nitro vendor puts it "More that 1% nitromethane by volume will require increased fuel delivery, when used in gasoline."

On the other hand this tendency to "lean out" might be an advantage as a chemical means to get a lean mixture to fully utilize the water injection's potential !!

Nitromethane burns quite slowly by comparison to gasoline so you will probably need more ignition advance to fully utilize the additional fuel.

The addition of water "should" tame it a bit, but I'd be worried about intake manifold explosions if you sprayed prior to the throttle body. If the engine hiccups and backfires into the intake manifold you might get to watch your intake manifold exit through the hood.

For those who have been to the drag races when fuelers are running the exhaust from a nitro burning car is very pungent ( contains a nitric acid mist basically) not good for your lungs so, be aware of the fact you need excellent ventilation and if your using any signficant amount, people will know it from the smell of you exhaust.

If anyone wants to experiment with this --- be VERY careful until there is a body of experience to tell you what is workable.

Nitromethane exposed to bright sunlite undergoes chemical changes and may perform unpredictably !!!

If used as a direct port injection setup it might be pretty good setup, especially for someone who wanted to avoid having a nitrous tank in the trunk but wanted the same sort of kick in the backside.


http://www.eskimo.com/~daddog/fuels/nitromethane.htm
http://www.turbofast.com.au/racefuel8.html
http://www.wediditforlove.com/techtalk4.html
http://www.cosbyoil.com/sunoconitro.html
http://www.pricechemical.com/nitromethane.htm
http://members.aol.com/FHSoil/FHSorder.html


Larry
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