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Remember that nitrous jet sizings are rated @ wheels on a naturally aspirated car. These gains are amplified on a turbo car..

So:

50hp shot would result in a 50hp@wheels gain on a civic.

50hp shot would result in a 75-ish hp@wheels gain on a turbo skyline

You can use either... I've used both wet and dry systems on my cars... Depends how big a shot you want to go and how big your injectors are... For you, I'd suggest a wet kit

Changing jets is cheap (they're only little brass restrictors), and most workshops will allow you to try different jet sizes to see which one you want...

I can guarantee that you'll go as big as you can, and end up with the 50hp jet :wave:

overboost store sells n-tercoolers and nos purge kits, dunno where in aus they sell em, but they are good with sales, usually cheaper too :D~.... is there any way of hiding the solenoids so coppers cant see em ????

yes you can hide the solenoids, I did it on mine.

I think we should move this thread to the 'wasteland' due to it's quality contributions and the fact that it isn't really about 'performance' at all. :)

Sorry guys I’m with Nath on this one, from a Chemistry point of view, O2 is replaced by NO2 in the combustion reaction….due to different reaction rates and energies of combustion on an atomic level. It has nothing to do with extra O2 being put in the engine, the power is from better combustion.

It’s rocket science ;)

Sorry guys I’m with Nath on this one, from a Chemistry point of view, O2 is replaced by NO2 in the combustion reaction….due to different reaction rates and energies of combustion on an atomic level. It has nothing to do with extra O2 being put in the engine, the power is from better combustion.

It’s rocket science ;)

What can I say? That's not right ;)

For starters, It's Nitrous Oxide (N2O), not Nitrogen Di-Oxide (NO2). Secondly, no O2 is being replaced, it's being supplemented by Nitrogen and Oxygen atoms, not Nitrous Oxide molecules. Nitrous Oxide never makes it to the cylinders. By the time it reaches the cylinders, heat has caused the molecules to decompose into their atomic states of Nitrogen and Oxygen.

Do you really think that the extra power produced "has nothing to do with the extra O2 being put in the engine"? So you're saying that if I injected twice as much air and twice as much fuel into an engine, I wouldn't make more power? Ooookay.

Yes, you get a cleaner combustion due to the denser intake charge from the Nitrogen component cooling effects. That plays a main part in the power production, but ignoring the Oxygen component is ridiculous.

Read my posts on the previous page to find out how each of these elements affect combustion and ability to make more power and torque.

Merli:

That was a typo about the nitrogen dioxide…lovely brown stinky gas ;)

Seriously though, I’m a chemist mate…I do know the reaction that N2O undergoes in a combustion process….and it has nothing to do with decomposition to O2.

N2O is extremely stable, if not inert at room temperature…above 300C it decomposes to N2 (molecular Nitrogen) and O* (atomic oxygen) which has nothing to do with O2 in any way shape or form. O* causes a free-radical oxidation of the fuel with is many, many times more energetic than the common or garden ‘internal combustion’ process.

In actual fact you don’t want any O2 in the cylinder as it reacts with O* to form O3 (ozone) which would reduce efficiency.

It is this free-radical reaction which gives you more power….if it broke down to O2 you’d be no better off than using air.

N2O does replace the O2, try flowing butane instead of N2O…”stallage” as no air is supporting combustion.

The only other ‘economical’ way of producing O* gas is by reacting Iodine with Hypochlorite….can’t see people running this in the boot.

QED

That's great, you're a chemist, but I doubt you know the exact workings of every bond and decomposition relationship of all the elements. Just like I'm in IT, I can't claim to know the workings of every piece of computer equipment in the world.

I however am not a chemist (apart from the 6 years of Chemistry at school ;)) but know exactly how the Nitrous Oxide in automotive applications work.

Nitrous Oxide doesn't break down into N2 and O... For every two moles of Nitrous Oxide (N2O) introduced to the cylinder, there are two moles of Nitrogen (N2) and one mole of Oxygen (O2)... It actually breaks down into 2N2 and O2, so there goes your whole argument.

2N2O -> 2N2 + O2

You are simply supplementing the amount of O2 in the cylinder that the engine can use to burn. It's very very very very simple.

"N2O is extremely stable, if not inert at room temperature"

Yes, but Nitrous isn't injected at room temperature is it? It's injected from the bottle usually in excess of 900psi and in a liquid form... When it hits atmospheric pressure, it immediately boils and causes a huge drop in intake temperatures.

Iodine, Hypochlorite, whatever... That has nothing to do with this and you're just waving your d1ck around trying to impress me aren't you? ;)

I may not know everything about chemistry....but there is a term called 'specialising' I know free-radical reactions, that's what it does...you can't change the laws of physics....BTW I don't remember mentioning heat of vapourisation when a compressed liquid boils? Yes it does get cold...liquid nitrogen anyone?

I really give up...that's just the way nitrous works...you just been mis-informed.

Dan

Where he's going wrong is that he thinks that it breaks down into N2 and O....

Which is incorrect. It breaks down into O2, and as you say "more oxygen... more fuel... car goes faster" ;)

Ok any cooling effect would be lost to the high exothermic reaction that is produced when you mix N2O, a hydrocarbon and an ignition source so it's not really applicable.

Oxygen (its the oxidizing agent in a combustion reaction) is not flammale on it's own and it needs a fuel source and an ignition source....just read an MSDS on it, again if it were oxygen availability then wouldn't pumping more oxygen into the engine make more sense even if its just an oxygen enriched compressed air?

It is all about thermodynamics and the stability of the end product from combustion (such as CO,CO2, H2O etc). Nitrous will immediately break down to nitrogen and an oxyanion (or more correctly radical as Dan states, my bad) as nitrogen prefers to be on it's own (more stable), the oxygen free radical can now have a few options 1.) It can rebond to a nitrogen molecule to reform nitrous 2.) It can rebond with another oxygen molecule (it is not stable bonding to just another radical to form oxygen as the quantum physics dont add up from this reaction) to form ozone or 3.) It can oxidize (donating the radical electron) the hydrocarbons producing an enormous amount of energy and forming very stable products such as water and CO.

If one was to look up the gibbs free energies of these reactions they would find that option number three will be the most favoured both thermodynamically, and from a stoichemetry point of view. Anyway this translates into more energy released per unit fuel.

N2O + Hydrocarbon + e- ----> N2 + H2O +CO + Heat

It really isn't possible to have pure oxygen produced by reacting two moles of N2O with the prescence of fuel, a spark, pressure and higher temp its just not thermodynamics or quantum physics.

This is a basic explanation off the top of my head (and now it hurts...hahaha) so please don't make me look up my 3rd year uni Physical Chemistry Books and give you an actual numbers.

"Inflammable means flammable......What a country!"

Man... You chemistry majors are making my brain hurt :D

And it's not fair that I'm bringing in HSC physics vs. your teritary level physics dammit!!! But I'm going to try anyway :D

Okay, firstly, Nath you said:

Oxygen (its the oxidizing agent in a combustion reaction) is not flammale on it's own and it needs a fuel source and an ignition source....just read an MSDS on it, again if it were oxygen availability then wouldn't pumping more oxygen into the engine make more sense even if its just an oxygen enriched compressed air?

Air has only 23.6% oxygen by weight, the rest is made up largely of nitrogen. That nitrogen does not aid in combustion at all, but it does absorb and carry heat away. When you add nitrous, it has 36% oxygen with the rest being nitrogen. So the more nitrous oxide you add, the less percentage of nitrogen is available to absorb heat. That is why nitrous increases engine heat very rapidly. If we were to add pure oxygen (which has been tried), the percentage of nitrogen would fall much faster as more oxygen was added. We would not be able to add much oxygen before heat was a problem to control. Also compressed oxygen is in a gaseous form, so adding oxygen takes up more room and reduces normally aspirated power, and the amount of nitrogen from it. By injecting liquid nitrous, the normally aspirated power only drops slightly and it is adding oxygen and nitrogen. To put it simply, with nitrous-oxide, we can get more oxygen atoms in the engine and have a lot more nitrogen as well. Nitrous-oxide instead of pure oxygen can make much more power before heat is uncontrollable.

Secondly, I read your post several times to make sure I got a grasp of what you were saying, and what you basically said was that the 2N2O --> 2N2 + O2 reaction wouldn't happen... Instead you suggest that N2O + Hydrocarbon + e- ----> N2 + H2O +CO + Heat would most likely occur.

So you're saying that by injecting Nitrous-oxide, I would get Nitrogen, Water, Carbon Monoxide and Heat????? How would that chemical result aid in allowing my engine to produce 100kw @ wheels more power? Theoretical chemistry is all well and good, and you can argue gibbs free engergies properties till the cows come home but I can tell you right now that Nitrous Oxide doesn't break down into Nitrogen, Water Carbon Monoxide and Heat. If you still don't believe me, let me take you for a ride in my car :D:):P

It really isn't possible to have pure oxygen produced by reacting two moles of N2O with the prescence of fuel, a spark, pressure and higher temp its just not thermodynamics or quantum physics.

Okay, well I don't know enough thermodynamics or quantum physics (eek3.gif) to even step into the ring with you here, but I have been using nitrous for the past 5 years or so, and between installing it on the first car (dry kit) and installing it on my latest car (wet kit) I have amassed quite a large knowledge base on nitrous oxide in automotive applications. Before playing with such a substance that could so seeming easily lift the head off my engine and send it into orbit, I ventured to read EVERYTHING I could find about the substance and how it is used in engines.

Some of my sources that I have read may very well be wrong, or even contradict your theoretical chemical properties, but I can tell you right now that it sure as hell isn't decomposing into an oxygen free radical and bonding to form ozone, nor is it reacting with hydrocarbons and electrons to form water, carbon monoxide and nitrogen.

dunno.gif

If you still don't believe me, let me take you for a ride in my car :D :D :D

I dont believe you... when we going for a ride? :P:)

Just curious what NOS kit you are using Merli? I am nearing the limits of my turbos but want to push out a bit more power (the engines rebuilt and should be able to handle it).

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