MustangWorks.com : Ford Forums - n2o...what do i need?

Here is a writeup I did a while back for another forum. Might be some info here to help you:

I thought I would share a little wisdom with this biggest bang for the buck mod.

There is no question that NO2 is by far the best way to add power to your car as cheaply as possibly. Most mods cost about $20 - $40 per hp. Think about it. This rate holds true almost everytime and is true for even the biggest mods such as blowers. NO2, on the other hand, can offer you 100+ hp and loads of trq for as little at $400.

Why is NO2 good? It does two things: 1 - It decreases the temp of the incomming air; 2 - It forces oxygen into the motor which allows for more fuel and thus more power. NO2 is like a chemical version of a turbo.

Why the bad rap? There are loads of horror stories out there of blown motors. Most of the time these are the result of people not knowing what they are doing and bad applications. Quite frankly, anytime you open a motor you run additional risks. A late model mustang a few weeks ago blew an engine right after a cam swap at Numedia Raceway. BAM!

Nitrous can be VERY safe if done right!!!

What are the downsides?
1 - Nitrous is cheap to install, but expensive to use. At $30 - $40 a bottle, it certainly adds up quickly if you use it a lot.
2 - Risk of severe motor troubles such as blown intake or burnt pistons (if not done properly)
3 - Nitrous is not as streetable as a blower as the boost runs out when the bottle gets empty (as well as for other reasons)

What are the bennefits?
1 - Cheap to install!
2 - Easy to remove and no one has to know it was ever there!
3 - Does not wear on motor when not in use. Blowers run all the time.
4 - Ideal for people that want a fast car, but not all the time such as when the wife is driving or the kids (can take out the bottle and disable)

There are two types of nitrous systems dry and wet.

Dry Systems: Dry systems spray nitrous in the intake and rely on the existing fuel system to add the proper amount of fuel.

Pros: Less moving parts with dry systems. Cheaper to buy and easier to install ($500+ for a good system). Less to go wrong. Can be very safe. Better for a beginner.

Cons: Considered more conservative than wet...not as much hp. If not enough fuel is added, you will go lean and burn up the motor.

Wet Systems: Wet systems add fuel separately and don't rely on th existing fuel system.

Pros: More Power! Can be very safe.

Cons: Many parts. Risk of blown intake by pooling of fuel in intake. More expensive to buy and install ($1300 for a good system).

So how do they work and what do you need?

For a Wet System, you need the following to truly have a great setup:
1 - Bottle Warmer: Ensures that the bottle pressure is ALWAYS constant. This will mean that you will have the same shot of nitrous each time and will ensure proper a/f.

2 - Purge Valve: Allows the user to rid the system of any air before using. This ensures proper a/f at initial spray.

3 - WOT Switch: This makes sure that the nitrous does not activate until the throttle is wide open. It generally gets signal from the TPS.

4 - Window Switch: This only allows the nitrous to spray between a particluar rpm range. This prevents spray at too low of rpms and if the rev limiter is ever hit which is an easy thing to do especially with 4.10's. If the fuel/nitrous sprays when the rev limiter is hit....BANG!

5 - Guages: Fuel Pressure and Nitrous Bottle Pressure are very useful.

Dry Systems all work a little differently from one system to another. But, they generally share one thing in common: They have a mechanism for pulsating the existing fuel injectors to add fuel. For example, The Zex system automatically controls bottle pressure so that it knows exactly how much nitrous is being added and then adds fuel accordingly.

The most interesting in the Venom-1000 (This is the one that I have). This system has a computer that monitors your a/f constantly and "drives" the fuel curve by adding fuel. It does not matter what your bottle pressure is or what size nozzle you use, it pulses the fuel injectors so that the correct amount of fuel is being added based on a/f. Sure, if you have a bottle warmer, you will spray more and the computer will then add more fuel as it always monitors the a/f. If the system goes too lean and the fuel can't keep up, it shuts down the nitrous.

Most dry system come with different sized nozzles that the user can add. They are generally from 25 - 150 shot which roughly equals a little less then that in hp.

How much nitrous can you add? As much as your fuel system will support. The general consensus is that the stock fuel systems on a GT (4.6) can support between a 100 - 125 shot. Bigger than that, and you need larger injectors and fuel pump.

I know I left some things out, but I thought this might be helpful for someone looking into nitrous.