Nitrous Purging

[2rismo]

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.

Holley (NOS), ZEX, Robbie Madden @ OzRace and just about every other performance workshop I have ever heard mention it disagree with you. To say that any cooling effect would be lost implies that there is one to begin with. Are you implying that there is a cooling effect that occurs but it doesn't cool anything? Or are you saying that it would be negligible?

I'm sorry mate but going by what you and others have said, the ideal would be injecting JUST oxygen into the combustion process. It's been tried before. In fact, the motor probably would've melted through the floor if it hadn't already popped the head off from the heat/cyl pressure.

Backwards logic or poor choice of words on your part.

Please enlighten me if I am wrong.

Adrian

[666DAN]

"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?"

Expanded hot gasses my friend they push pistons normally don't they? The volume occupied by superheated gas, which = Heat + Water, Nitrogen, Carbon Monoxide is greater so more pushing power = your extra 100Kw. That's what fuel normally decomposes into...so why would you think any different just because nitrous is in there too?

Also it has a lot to do with the speed of the expanding flame front, which with a nitrous oxide reaction is steadier...where if it was decomposed to O2 the reaction would be quicker and uncontrolled (detonation)

BTW The heat capacity of Nitrogen would have next to no effect on removing heat.

Dan

[nath_gtir]

I may hold you for the ride in the car one day. BTW you can get instrument grade nitrous for cheaper then the shit you buy at autobarn (99.9999% pure).

[Merli]

Expanded hot gasses my friend they push pistons normally don't they? The volume occupied by superheated gas, which = Heat + Water, Nitrogen, Carbon Monoxide is greater so more pushing power = your extra 100Kw. That's what fuel normally decomposes into...so why would you think any different just because nitrous is in there too?

Also it has a lot to do with the speed of the expanding flame front, which with a nitrous oxide reaction is steadier...where if it was decomposed to O2 the reaction would be quicker and uncontrolled (detonation)

Heat, Water, Nitrogen and Carbon Monoxide is the result of normal combustion, correct. Or are you saying that's what Nitrous-Oxide forms after superheating due to hitting atmospheric pressure and boiling? I sure hope that's not what you're saying :looney:

Perhaps we're getting our wires crossed... I'm talking about what happens to the Nitrous-Oxide BEFORE combustion. You're saying to decomposes into Oxygen Free Radicals, and I'm saying that's incorrect. It forms 2N2 + O2.

I don't disagree that AFTER COMBUSTION, it forms N2, CO, H2O and heat... That's normal combustion, because the nitrous-oxide has broken down into 2N2 and O2.

BTW The heat capacity of Nitrogen would have next to no effect on removing heat.

Well I'm afraid that there are several nitrous oxide manufactuers who disagree with you 110% on that fact :Oops:

[Merli]

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

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).

At the moment I'm using a Holley (NOS) Wet Kit, with a single fogger running a 30hp shot on my GTR... and it has resulted in a 35awkw power increase and MASSIVE torque increase... After the engine is built (hopefully soon!) I will push this to 75hp shot and hope for 80awkw increase...

With forged pistons (I'm using GREX 87mm pistons) they should be able to handle the incredible in-cylinder pressures and temperature increases seen by a nitrous shot... Stronger conrods would help too at high revs

Best is to have a direct port setup, with individual jets shooting down each intake runner, but the minimum you can run then is 25hp jets on each cylinder = 150hp shot all up AFAIK... Maybe there are smaller individual jets available now...

Doughboy has told me about a plate that fits around the INJECTOR collar that squirts nitrous in where the injectors are, which I would be very interested in... Means no drilling your intake plenum for direct port injection!!!!

[666DAN]

I was talking after combustion?

Seriously have you guys ever heard of O*, maybe that's the problem here, you've never heard of radical reactions...so are going with the O2 story?

If you've got the same amount of fuel being burnt...how do you explain the massive increase in energy you get from using the nitrous...you'd get a bit more from the leaner burn...but the bulk comes from it being a radical reaction instead of a conventional 'burn'

"BTW The heat capacity of Nitrogen would have next to no effect on removing heat."

Liquid nitrogen would....but why would a 'nitrous' manufacturer comment on nitrogen....oh wait that wouldn't be a conflict of interest at all would it "Buy my product"

I'm soo over this whole thread......

You better go and check that the world is still flat boys!

[Merli]

If you've got the same amount of fuel being burnt...how do you explain the massive increase in energy you get from using the nitrous...

Holy Jesus........................ same amount of fuel?!?! You *DO* realise that you inject a lot more fuel in with the nitrous right?!?!?!

[nath_gtir]

I could go on and on here so lets just agree to disagree everyone has an opinion, who you believe is up to you!

[2rismo]

If you've got the same amount of fuel being burnt...

Jeeeezz!!! And WE'RE the ones that have missed the point?!?!?!

I think you missed the reading comprehension boat!!!

I would refer you to my earlier post (and a highly technical and calculated one at that)

"More Oxygen gets into the combustion chamber - allows you to burn more fuel - unleashes more energy - car goes faster."

Umm.... I am at a massive loss to work out how you missed the whole point. And as for the world being flat bs, stick it up ya burette.

Adrian

[666DAN]

So I'm assuming all you guys have adjusted your fuel MAPS to cope with the nitrous...if not and you expect the ECU to figure it out then you're more misled than I thought.

2rismo, yeah you are at a massive loss!

[Laurence]

Learning is fun...

Wet nitrous systems add the fuel in as well...

[666DAN]

What about fogger kits though?

[666DAN]

Anyway I agree with Nath, as far as you guys are interested, NOS + Fuel in engine = vrooom....so I should probably leave you with that.

It's not how it works that's important to you lot...it's that you know it's doing something.

BTW

"Probably the most familiar free-radical reaction for most people is combustion. In order for combustion to occur the relatively strong O=O double bond must be broken to form oxygen free radicals. The flammability of a given material is strongly dependent on the concentration of free radicals that must be obtained before initiation and propagation reactions dominate leading to combustion of the material. Once the combustible material has been consumed, termination reactions again dominate and the flame dies out."

taken from http://en.wikipedia.org/wiki/Free_radical

As N2O breaks down into purely free radical O* as I said before.... the flammability of the fuel is increased = more energy output.

If you can't believe published work...then there is no helping you

Dan

[Laurence]

As an Electrical Engineer the voodoo of chemistry has always escaped me. Especially catalysts for reactions, bits of metal just hanging around getting atoms to react very strange... But I digress. I am happy with the idea of O* busily reacting with everything, NOS the company explains the reaction as breaking down to N2 and O2 which also makes sense to me.

I think we just need to get a big chunk of platinum in this forum and then we will all bond.

p.s. A dry system does require the ECU to inject more fuel.

[666DAN]

That's what I've been trying to get across, that there is a more complex way that these reactions undergo. That's why some guy at NOS isn't going to sit down and explain the ins and outs of a radical reaction...chances are he doesn't know, he just knows it gives more power..and basically wants you to buy it.

I was trying to give an insight into it but just got a load of smart remarks.

Just try and accept that sometmes what you have been told isn't the full story.

Dan

[Merli]

So I'm assuming all you guys have adjusted your fuel MAPS to cope with the nitrous...if not and you expect the ECU to figure it out then you're more misled than I thought.

2rismo, yeah you are at a massive loss!

Ignoring the chemical debate for a minute, going by the above post, it's completely clear to me now that you are completely oblivious as to how Nitrous Oxide works in an engine.

[Merli]

p.s. A dry system does require the ECU to inject more fuel.

Not usually. Most Dry kits just use another solenoid to bump up fuel rail pressure to supply the needed fuel.

If you're using more nitrous than is safe to bump the fuel rail pressure upto, or you're going past max injector duty cycle, you should be using a wet kit, and most probably a direct port injection kit.

They only changes needed to the ECU is perhaps ignition retard depending on how much nitrous you're using.

[Merli]

"Probably the most familiar free-radical reaction for most people is combustion. In order for combustion to occur the relatively strong O=O double bond must be broken to form oxygen free radicals. The flammability of a given material is strongly dependent on the concentration of free radicals that must be obtained before initiation and propagation reactions dominate leading to combustion of the material. Once the combustible material has been consumed, termination reactions again dominate and the flame dies out."

That is talking about combusting atmospheric air, and it talks about breaking hte bond of an oxygen molecule into oxygen free radicals.

Nowhere does it state that Nitrous Oxide doesn't decompose into O2 molecules and then undergo the same combustion process...

Why do I constantly have to rebutt the obvious?

[rev210]

During the combustion process in an engine, at about 572 degrees F., (on compression stroke), nitrous breaks down and releases oxygen ions. This extra oxygen creates additional power by allowing more fuel to be burned/oxidised. Nitrogen acts to buffer, or dampen the increased cylinder pressures helping to control the combustion process. Nitrous also has a tremendous "intercooling" effect by reducing intake charge temperatures by 60 to 75 degrees F. However, it is not this oxygen alone which creates additional power, but the ability of this oxygen to burn more fuel. By burning more fuel, higher cylinder pressures are created and this is where most of the additional power is realized. Secondly, as pressurized nitrous oxide is injected into the intake manifold, it changes from a liquid to a gas (boils). This boiling affect reduces the temperature of the nitrous to a minus .127 Degrees F. This "cooling affect" in turn significantly reduces intake charge temperatures by approximately 60-75 Degrees F. This also helps create additional power through greater density. A general rule of thumb: For every 10 Degrees F. reduction in intake charge temperature, a 1% increase in power will be realized. Example: A 350 HP engine with an intake temperature drop of 70 Degrees F, would gain approximately 25 HP on the cooling affect alone. The third point, the nitrogen that was also released during the compression stroke performs an important role. Nitrogen acts to "buff or dampen" the increased cylinder pressures leading to a controlled combustion process.

[Merli]

I've put up this page real quick...

http://www.fortheboyz.com/tech/nitrous.php