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OH NOEZ
01-29-2003, 05:02 PM
What exactly is nitrous? How does it work? Why does it work? How much nitrous can I run? Is nitrous expensive? What kind of setup do I need? Who makes the best kit? What are the different types of kits?

I will do my best to try to answer all of these questions.

First, let's start out with some basic engine theory. Your motor makes power because it takes the heat energy created by combustion, and turns it into mechanical energy. Combustion is simply the rapid oxydation of fuel. The more air and fuel you can cram into your cylinders, the more power you will make. The ratio's in which these two components are added, however, must be kept within a certain range. For arguements sake, however, we'll say that you are adding the two in the correct proportion.
Nitous is an oxydizer, which is an oxygen-bearing chemical that has more easily available air than atmospheric air.

Air is 23.6% oxygen, and nitrous is 36% oxygen. However, we can't forget that nitrous is much more dense than air at room temperature, so pound for pound, nitrous contains much more oxygen.

The stoich ratio for air/fuel is 14.7:1. This is, however, NOT the stoich ratio for a nitrous powered motor. In order to completely burn the air/fuel/nitrous mixture, the ratio should be somewhere around 8.5:1.

We've talked about alot about nitrous, so let's talk about it's "Better Half", or fuel. In order to keep a safe nitrous burn going, fuel must also be injected with the nitrous. Because Nitrous already has oxygen in it's chemical composition, fuel must be injected independently to keep you from running lean (too much oxygen) and potentially harming your engine.

Now on to the actual kits. There are MANY companies that manufacture nitrous kits. Some of the most popular are NOS, Nitrous Express, Nitrous Works, Zex, and TNT.

The kits are all fairly similiar, but there are a few exceptions. The NX (Nitrous Express) solenoids are the biggest, and therefore, can be the safest. The NOS solenoids are small, but you can upgrade them for larger units. The Zex kit is a dry kit (No fuel added) so the amount of nitrous that can be added is kept at a minimum.

Zex likes to advertise that there 'Purple Box' keeps everything under control, but I've read a few stories of where the box failed, the motor went lean, and proceeded to either blow up totally, or burn a hole through the piston. If it were my car, Zex would be my last choice.

There are two setups you can order from almost any company. The first is a 'wet' kit and the second is a 'dry' kit. A wet kit has both fuel and nitrous solenoids, so it injects both fuel and nitrous. This is the safest way to run nitrous. The second way to inject nitrous is through a 'dry' kit. This kit doesn't inject any fuel, so you must keep an eye on your air/fuel ratio, and keep your nitrous on a low shot.

One of the biggest questions about nitrous is, 'How much can I run, and still be safe?' Well, the answer is quite simple.

First, you'll need a new clutch, FAST. Nitrous will kill the stock one in a hurry. Second, you'll need some new spark plugs. NGK V-Power's are my personal recommendation. I've heard nothing but great things about them. Depending on the size shot you want to run, a blockguard, spark plugs wires, or a fuel pump might be required. Anything over a 100 shot should be accompanied by these three accessories. The money you spend on these will be well worth the 'insurance' they can can provide.

If your running an aftermarket ECU that tends to lean the motor out, you'll definately want to get a fuel pressure regulator to keep your air/fuel ratio in the safe zone.

Other than that, you should be set.

If you've got any more questions, feel free to post them and I'll do my best to answer them.

If I've messed up anywhere (I'm sure I have) feel free to correct me.

Enjoy.

SHIFT_KA
01-29-2003, 05:07 PM
nice FAQ

OH NOEZ
01-29-2003, 05:20 PM
Originally posted by SX GYRL 97
nice FAQ

Eh. :afro:

JDMhatchback
01-29-2003, 05:39 PM
copy and paste =)

crX-RATED
01-29-2003, 05:40 PM
Originally posted by JDMhatchback
copy and paste =)

OH NOEZ
01-29-2003, 05:42 PM
Incorrect.

Slim ThuG
01-29-2003, 05:48 PM
thanx for the info Professa'

Powell
01-29-2003, 05:57 PM
Corrections..

A dry kit is usually sprayed before the MAF on a stock car so that the computer will take into effect and richen the car up. On a Mustang you can spray up to a 150 shot with a better fuel pump. The only times you see a dry kit after the MAF is if the computer is tuned to run rich when the n2o is on.

TNT has almost the same size solenoids as a NX kit

Wet kits are almost always placed close to the throttle body so that the n2o/fuel dont have to travel around corners in your intake.

OH NOEZ
01-29-2003, 11:42 PM
Originally posted by Powell
Corrections..

A dry kit is usually sprayed before the MAF on a stock car so that the computer will take into effect and richen the car up. On a Mustang you can spray up to a 150 shot with a better fuel pump. The only times you see a dry kit after the MAF is if the computer is tuned to run rich when the n2o is on.

TNT has almost the same size solenoids as a NX kit

Wet kits are almost always placed close to the throttle body so that the n2o/fuel dont have to travel around corners in your intake.

I really didn't wanna talk about the TNT kit because it's mainly for domestic application's, so I figured it wasn't too relative.

The dry kits I've seen for imports are injected in the same spot as a wet kit. I guess I've really only looked at the Zex dry kit though.

SecretAgent
01-30-2003, 12:18 AM
It is now common recommendation by most kit manufacturers to put both wet and dry kit nozzels as close to the TB as possible.

and powell, while the nozzle before the MAF works on some cars, if you have a heated element MAF (can't remember the name, but it's basically just a thermistor) you're screwed. You do that on one of those and you crack the resistor, and you're out a few hundred bucks for a new MAF and possibly a new motor. The thermistor can't handle the extreme temperture drop the nitrous exposes it to. It can only handle the gradual increase/decrease in temp that a normal motor experiences. If you try to shoot -280 degrees F nitrous on to it, you may as well take it out and beat it with a baseball bat, the effect will be the same.

another important consideration is the nozzle itself. each company uses it's own style of what they think is the best. I prefer NX, as do most other enthusiasts. They've been proven to flow more and atomize better than the other nozzles out there.

A proper a/f ratio is never (well, almost) 14.7:1. most cars like to run a lot richer than that. the only time you should be running 14.7:1 is at idle, or light load situations. under full load you want to run anywhere from 11:1-13.5:1 depending on the motor, setup, conditions etc.

Some other things out there are plate and direct port systems. Plate system as extremely convienient. Install time is a breeze and there are no holes to drill and/or tap. The install is completely irreversible, and depending on the system often a plate system will distribute the nitrous/fuel mixture better than a nozzle system. Direct port kits are by far the best out there tho. The ensure that all cylinders are getting the exact flow of nitrous as every other cylinder, therefore making it safer to run larger shots where you're dumping in a lot of fuel and run the risk of puddling fuel in the intake.

I think that's about it.

Oh, nitrous is 33.3% Oxygen. not 36%. and 23.6 or whatever O2 content in air is being optimistic, generally you see 20.5% max.

OH NOEZ
01-30-2003, 12:22 AM
Correct me if I'm wrong Donnell, but isn't it true that there is a limit to how much you can spray on a single fogger system? I guess that would be another advantage to the Direct Port setup.

SecretAgent
01-30-2003, 12:28 AM
common consensus is usually around 150. I wouldn't go above 125 tho. But some people have had good luck running that much or more through a single fogger. But, if I can afford to run that much nitrous, I'm going to flip the couple hundred bucks extra and run direct port. If nothing else, for the piece of mind. I don't like pushing things to the limit, at least, not like that.

T-67 turbo GSR
01-30-2003, 10:11 AM
i wouldnt go past 75 -100 on a single fogger. wet!
dry id stay at 80 max. ...4banger application.
in my experience, it seems you can get away with a lot more on a dry shot for some reason opposed to a wet where the pump has to feed both the injectors and the nozzle..strange...stock pumps. direct port is my method of choice...forget a single fogger unless you are turbo'd...limits to applications usually reflect what your car can accurately distribute to individual cylinders:baby: