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If you follow the top-fuel dragster comps you'll know what this is, but for those that don't its CH3NO2. When it burns, it's more efficient than gasoline in that it provides its own oxygen molecules, two per CH3NO2 unit. However if you were to run nitromethane in an ordinary car, you'd blow the system to bits simply due to added pressure and the fact that nitromethane never burns completely in a stroke. It also adds to alcohol accumulation in the filters etc. Oh and when nitromethan burns you'll never see it coz it's flame is invisible (so you'll only find out when your car burns or it gets really hot for no reason).

Now my question is this... what happens if you say mix 1 litre of nitromethane to 49 litres of gasoline. Or better yet, use an ordinary fuel pump system to boost your fuel lines with a nitromethane shot. Its easier to store and inject since its a liquid at room temperature, and theoretically should work better than Nitrous since its chemical composition is N2O (one oxygen molecule).

From what I can see, the fact that Nitromethane is a liquid means that its denser than Nitrous at room temperature, meaning you can get MORE into the engine. (I realise an engine and underbonnet is not the same temp as room temp). Also when Nitrous is used, it releases 1 atom of Oxygen, wheras Nitromethane releases 2 atoms. Which means Nitromethane is twice as potent. Also nitromethane contains a CH component which will also boost combustion.

I realise that Nitromethane has already been developed to be used in top end dragsters, but is there a suitable or safe way of using it in a standard combustion engine?

Some interesting facts...

Air = O2 20.99% + N2 78.03% + A 0.94% + CO2 0.03% + H2 0.01%

Gasoline = C8H18

Complete Combustion: C8H18 + O2 + N2 = CO2 + H2O + N2

Air Fuel Ratio = Mass Air / Mass Fuel

AF = 15.1 Parts Air for each Part of Fuel

Nitromethane = CH3NO2

Complete Combustion: CH3NO2 + O2 + N2 = CO2 + H2O + N2

AF = 1.7 Parts Air for each Part of Fuel

788% More nitromethane is burned compared to gasoline per volume of air.

http://auto.howstuffworks.com/question642.htm

Also this is a real fact: the first use of Nitrous was in WW2 where the Nazi's used Nitrous to boost the power of their engines in their aircraft, which meant they flew much faster than their British or American counterparts. They were the first to develop nitrous injection into the airways of a combustion engine to boost its oxygenation.

I will call Dinitrogen monoxide NOS for simplicity sake

Combustion formulas:

Gasoline: C8H18 + 34 O2 = 8 CO2 + 18 H2O

Nitromethane: 2 CH3NO2 + 10 O2 + N2 = 2 CO2 + 6 H2O + N2

Gasoline + NOS: C8H18 + 12 N2O + 11 O2 = 8 CO2 + 18 H2O + 7N2 (given a 1 part oxygen to 1 part NOS composition with bias to NOS)

Gasoline + Nitromethane: C8H18 + 8 CH3NO2 + 9 O2 = 9 CO2 + 21 H2O + 4 N2

So as you can see, IF you ran a 1 part fuel to one part NOS mixture you'd need 12 NOS molecules and 11 Oxygen molecuse for complete combustion.

But with a 1 part fuel and 1 part nitromethane mixture you'd need 8 molecules of nitromethane and 9 molecues of oxygen for cumbustion of the same amount of fuel. Which should prove that nitromethane is a BETTER fuel booster than NOS.

Also note that N2 is produces in ALL combustion engines due to the high temperatues, and have not been taken into consideration in these formulas.

The RC fuel isn't pure BTW.

It's a mix of nitro, castor oil, and something else can't remember so you couldn't use in a car unless you wanted it smoking and probably stuffing things inside the motor as well.

The mix goes like this.

5 to 30/40% nitro

75 to 50/60% castor oil

and the rest is the other stuff

The mixes always add up to 100%

no no, i'm not talkin about putting RC fuel in your engine, that's silly coz RC fuel is made to lubricate and power a 2 stroke minature engine.

I'm talkin about a 1 litre tank of 100% Nitromethane, for use very similar to a shot of NOS, but mixed with the fuel pre-delivery for a very similar effect.

N2O tanks aren't cheap so I'm assuming pure nitromethane would cost around the same, but it'd be a tad cheaper than than N2O since its easy to manufacture and source nitromethane.

This thread has nothing to do with RC cars or the fuel mixture they use so don't refer to them in future posts.

As I said before the RC fuel is cheap because they don't need to use a lot of nitro in the mix, so a 44gal drum would be enough for 1000 bottles of RC fuel depending on the mix.

I would think it would be dearer due to it not being used much.

Resultant heat could be a problem, the top fuel drag car's engine have to be cut from the fuel supply before the engine stops, There's enough heat to keep everything ticking over, so what you might find is that the heat might keep the fuel combusting over and over, making your engine work faster and faster, unless you cut the fuel supply.

That or your block might just melt or crack or warp badly, would need all new internals etc so they don't melt etc.

Is this because of the fact that you can never get 100% nitromethane to ever combust completely in one stroke of a piston?

What would happen if it was used as a shot like N2O?

Are you aware that the correct A/F ratio's for nitro are not the same as petrol? ie,if you inject your "shot" at the very least you would have to have extra injectors come in at the same time.Also,I think that injecting raw nitro would be a bad idea,as even the big alchol boys mix it in a base of methanol,and all this stuff corrodes stell fuel lines/tanks,etc,and turns to a thick jelly-like sludge if left for any length of time :D

And isn't nitros oxide N2O3?.......

I seem to recall reading that nitromethane is extremely destructive to engine oil, it causes it to break down somehow. This is no problem in an AA fueler because the oil gets changed very frequently, but it may cause some problems if you expect 5,000 Km oil change intervals in a road car.

I may be completely wrong about this, but it may be worth looking into.

A very interesting idea to be sure. Maybe some additional injectors with nitro/petrol mixture could just be switched on or off. They could be driven at the same duty cycle as the main injectors when turned on ? It would then be a case of adjusting the nitro/petrol ratio and injector size to give the required power increase at the correct air/nitro/fuel ratio on a dyno.

from all the sources I checked N2O was the formula for NOS

also are there any possible issues with mixing a small amount of nitromethane in your fuel as say a fuel additive to give it that extra zing? s there any reaction between gasoline and nitromethane?

I'm aware the concentration of NOS in the engine at time of combustion is very little, what if the nitro methane was added tot he fuel lines in a similar small concentration. Would this still corrode the fuel lines? I guess you'd have to make sure there's just enough to completely combust in a cycle or any uncombusted nitromethane is sent out thru the exhaust.

I saw your post, and your idea is definitely very pleasible, provided the system is able to take it. Oh, and if you mix it, you'll need to look at the relative weights, and if they their degree of solubility. Otherwise one might sit on top of the other.

testing

I'm not giving anyone any ideas here. But, this is how the guy tested the SYB. he hired a rental car for a day. like a new commodore or something with variable valve timing. Then the effect of your idea will kick in much quicker. Not like how with our engines we have to reset ecu, then dyno tune.

I'd say, if you are going to test, you'll probably be best to do a pwoer test across the range. Look at the shape of the curve as well. Then add a mild amount to the fuel tank, and try. may require tuning. This will show if there is any perfomance increase.

In regards to intake injection, you can always try it too. Remeber about safety though. Also, how will you volatise it? i imagine it will be injected behind the filter too?

In regards to in the long run about oil, and filters, I think we need more research and if anyone else has any experience about this.

i'm really interested in your ideas mate, as nitrous kits seem very expensive, and from your equations, this seems to do the job.

Just need to work out a method of injecting it, and it should be good. Home made nos kit. Plus, i like the idea of how your fuel is liquid. Much safer and also gives the option of injection, instead of vapourising the air intake.

Another thing to look at would be the nos brand fuel additive to see what they have in it. Because if it's the same, it might be safe to just add it straight t o the fuel.

so in no time, we may have a nos system costing $15 a litre, which should last a reasonable time. That is compared to nos, costing $1 a sec for a 100 hp unit.

Oh, another thing to keep in mind, i've known a few people with the wet nos systems. Actaully, 2rismo knows as well, he pulled an 11 sec pass with wet nos system. You have to tune your car to the nos. That means that when we are using it, say if we press the button to inject it, it will run nice (provided it works). But then when we choose not to, it will be out of tune. (poor performance). Therefore, adding to fuel will be alright, since it will always be using, not like pressing a button to inject. But then most likely, it will not be as strong, as you don't want it to be running high levels of the stuff all the time, or you're blow you're turbo due to the extra heat out the exhaust. 2rismo says this too. You must cool down after doing a pass with nos. So there seems to be a bit of a tradeoff. hmmm. big power, then crap performance when off the fuel, or mild performance always.

just a few ideas mate.

from all the sources I checked N2O was the formula for NOS

.

Dunno about the rest of the stuff here, but i know that N2O is right - O has -2 valence, N, while noble, has 1 outer shell electron which covalently bonds with each O valence electrons, hence 2 N for every O.

i think.... been a while :confused:

Basically, the chem looks sound - Now just need 4 gallons of nitro and a rent-A-car.....

Now just need 4 gallons of nitro and a rent-A-car.....
Cant resist, it has to be said... "I poot bomb in car and blow you to sky!".

I can rig up a ECU system that runs with 2 fuel maps pretty easily with a bot of solder and a switch.

One of my mates is currently working with a guy on fitting an RB25DET into an FJ Holden (which is VERY non ECU friendly) and reprogramming it to work with it. I can ask him to reprogram 2 stock ECU's one with a fuel map for no additive and one with. Switch the car off, flick the switch and presto, instant fuel map.

Or use a Power FC and use one of the multiple fuel maps you can program into it.

So yeah, managing fuel maps for varying compositions isn't that hard.

My greatest concern would be:

a) the effects of nitromethane or ethyl alcohol on gasoline and its additives.

B) the effects on the components of the car and safe limits to which it can be used

c) finding the correct concentration to inject

Also as for the NOS fuel additive you'll find that its just a marketing ploy to make it sound good by association. Betcha its just a regular octane booster.

I'm assuming Ethanol would be similar. I'd assume its a lot easier to get (at any chem lab supply centre, then purify it to get rid of the poisons added in to stop people from drinking it). but being a pure alcohol (C2H5OH) is still less potent than nitromethane, but its availability might work towards its advantage.

Also seeing that many dodgy petrol stations have mixed ethanol (in small quantities) to petrol to water it down, it can't have a bad reaction with gasoline, so might be better suited to premixing.

I'm leaning towards the pressurised shot system for the nitromethane, as I don't think it would be worth the trouble to run it as a fuel additive. It would be far more useful in a shot system on the drag strip.

Remember trying it once in my friend's old commondoor... Made a 5% nitromethane/95% leaded mix and fed it into the thing. (He used to fly pro R/C airplanes and had plenty of the stuff, just had to make sure it hadn't turned purple!)

Nothing was retuned or anything, just having some fun. It did give a noticable seat-of-the-pants kick, not much I'd say it felt like 5-10kw? He's done it a few times (say 5) and the engine's still running 5 years later. We never wanted to run it above 5% mix though, he knew the engine wouldn't want too much more!

Now if you remapped your ECU for it, it'd be quite interesting!

The nitromethane you guys used, in R/C aeroplanes, that's the same type I'd use in my R/C dosen't that have castor oil n stuff in it? Did you notice any change in the exhaust gasses?

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