Can someone give me a rundown of HOW you engage nitrous?

[integra818]

I've learned a thing or two about nitrous in the past, how it's made, how it works, but one thing I don't know is HOW you turn it on. From my understanding, you open the bottle, and nitrous fills up the lines, when you press the engage button, the solenoids open letting nitrous into the engine. Now...how do you turn it off? Do you close the bottle and press the nitrous button to get all the nitrous out of the lines or how do you do it? Someone please explain.

[Sluttypatton]

A solenoid is an electronic valve, and the ones used in nitrous systems are closed by default. This means that they are always closed unless you complete the circuit (press the button) and supply the current needed to open the solenoid. The result is; the moment you press the button, the solenoid opens allowing nitrous to flow (as long as the bottle is also open), and the moment you release the button the solenoid closes, and nitrous stops flowing. And it is that simple for a basic nitrous setup (one without a purge valve, or any nitrous controllers). So the basic sequence is; open bottle, activate nitrous at the correct time, let go of button when you no longer need nitrous.
On a setup with a purge valve, the sequence becomes a little more complicated, but remains essentially the same. First you open the bottle, then you purge the lines (purging is just sending a short blast of nitrous through the lines, and outside the car to clean out the lines before use), then press the button when you want your nitrous to be activated, and let go when you don't.
There are other variables too, some people have their nitrous switches placed under their gas pedals so when they accelerate under WOT, the switch is depressed by their foot along with the pedal, however this is a less common placement for the switch.
There are also nitrous control systems that change how the nitrous is activated by starting flow at a set level (anywhere from 0%-100%) and working up to full flow to minimize wheel spin while launching.

[integra818]

So can I have the bottle open the whole time and have it engage only at W.O.T. and not worry about nitrous leaking into the engine?

[2turboimports]

yah...there are numerous kits with computer controlled solenoids. 1 kit has a setup so that the solenoid only opens at preset settings. For example a 50 shot to be sprayed ONLY at 80% throttle @ 4500rpms. Those kits typically come with another solenoid you tap into the fuel line so that when the nitrous solenoid opens, additional gas can be sprayed with the shot. i think that's called a wet shot.

[Sluttypatton]

Yes, I suppose so, but for safety's sake you should always close the bottle when you no longer need to use it. The most convenient method is to buy an electronic bottle opener, this allows you to open and close the bottle without leaving your seat. This, however, may be illegal depending on where you are; where I live I think the law states that the bottle may not be accesible from the cockpit, remotely or physically. The reason for this is so spontaneous street racing is much more difficult, after all it won't work very well if someone wants to race at a stoplight and you have to get out, go to your trunk, open the bottle and then race.
Only open the bottle when your going to use the nitrous, just to be safe. Don't worry though, when the bottle is open it won't leak into the motor until you push the button, and as soon as you let go of the button it will stop flowing automatically...unless your solenoid is defective.

[integra818]

sluttypatton, a Civci cranked his engine at the dragstrip before the burnout box and the car's engine blew up. What could've caused this? My friend told me that he had a nitrous leak and the engine was filled with nitrous when he started the car. Can you help me understand what the hell happened so I don't do it to my car.

Oh, another thing, where the hell are the jets located? In the solenoids or what?

[Sluttypatton]

Do you know specifically what happened to the motor? What part of the motor suffered damage? Were the pistons windowed?

As for the jets, they are inserted into the nitrous line to meter flow. The hole is usually measured in thousandths of an inch. So one would use a larger jet, say a .040 rather than a .035, if they wanted to burn more nitrous.

[integra818]

It was a while ago, memory a little fuzzy. But I imagine he blew a head gassket from so much pressure in the cylinder. I doubt he broke a rod or something.

[Sluttypatton]

It is difficult to say what actually happened without seeing the wreckage, but one thing is certain: If the damage was nitrous related it was either due to a malfuntioning solenoid or driver stupidity...possibly a bit of both. Either the solenoid leaked, or he engaged the nitrous, it doesn't really matter which as they have the same effect. This isolated and rare incident should not put you off nitrous, it is quite unusual. I would suspect that if it was a solenoid failure, it was due to improper (or nonexistant) filtration of the nitrous, causing a small particle to block the solenoid open. Another thing to think about is whether or not the damage was nitrous related, as I am not even sure if it would be possible to start a nitrous flooded engine, as there would be no combustion temperature to break the N2O into nitrogen and oxygen. N2O will not support combustion until it has been broken down into N and O2, so the engine would probably not start until the nitrous had been cleared out of the cylinders. Don't take my word for it though, I have never been unfortunate enough to have to test this theory, so it is entirely possible I am completely wrong.
Properly used, nitrous can be quite safe, and there are extra precautions you can take to make it extra safe. I would advise getting the extras that make it a little safer, the most important extra being the fuel pressure safety switch, this prevents a fuel system failure from causing a lean condition that destroys your engine by shutting off the nitrous flow as soon as fuel pressure drop is detected. A purge system is a good idea too, so that the nitrous lines are cleaned before use, helping to prevent solenoid jamming.
It's hard to go wrong with nitrous if you use it properly, and decide upon a conservative shot.

[integra818]

I'm not 100% noob. I've been interested in nitrous for a good 5 years (before any street racing movies came out showing nitrous in action), reading a few things here and there.

About this fuel pressure saftey switch, can it be used with the NOS sysem? I'm not sure if it's NX that has it or ZEX, but one of them has a system that shurts off the nitrous flow as soon as the A/F ratio leans out. Can you use that switch with the NOS system?

As far as I know, these are all the things reccomended before using nitrous:

1. Spark plugs, I've been told Bosch sucks, NGK is the best

2. Rev limiter, to prevent nitrous going into your engine in over-rev conditions

3. ignition box, altough I have no idea why.

4. a good head gasket

5. 91 octane or higher gas

What else do you reccomend sluttypatton?

Another thing. This might be a little complicted. I've heard that you have to retard your timing 2 degrees for ever 50 shot(or something like that), but let's say that we have a Mazda miata which makes it's peak power at 14 degrees btdc, but it's set by the factory at 10 btdc. Could I just leave the ignition timing alone if I were to use a 50 shot system? But I'm not sure if the miata timing is btdc or AT tdc.

I appreciate you teaching me all this stuff. If you're getting annoyed by this, you can ignore my questions and I WILL NOT take offense to it.

[Sluttypatton]

I am by no means an expert on nitrous, but I am more than happy to share what I know. Anyone else, feel free to pipe in and correct me if you feel I'm wrong somewhere.

FPSS's are sold by every major nitrous company around, so there is no problem there. I don't see why they wouldn't be universal, but I am not sure.

1) It doesn't really matter that much as long as the spark plugs are good ones. The general rule of thumb is to go 1 or 2 heat ranges cooler than your stock plugs. Also, the best spark plug is generally the one with the smallest electrode, it will give the best spark, but will wear quicker. Iridium spark plugs allow for a smaller electrode as the material is consumed less rapidly. Avoid gimicky spark plugs like the ones with four electrodes, all they do is cover the spark from the majority of the air/fuel mixture and make igniting the mixture more difficult.

2) Not sure about this one, but I guess it can't hurt. As long as you exercise a little caution when using nitrous, this is an item you could go without.

3) Definately a good idea to upgrade your ignition, unless your car has naturally kick ass ignition. While using nitrous, it's going to be harder for you spark plugs to deliver a strong spark. An MSD (or equivalent) system can help make sure the fuel is ignited properly.

4) A good head gasket is a good idea for any car, don't change your head gasket because your adding nitrous to your car, change it when it needs to be changed. A head gasket will (generally) only be damaged by detonation, and if your detonating, you should worry more about your pistons than your head gasket.

5) High octane gas is a must to avoid detonation while using nitrous. Get the highest octane gas you can get your hands on when you plan on using nitrous.

Other than that, just make sure you motor is in good shape, don't nitrous a worn out motor...

I don't have much experience when it comes to ignition retard, I am lucky enough to own a knock sensor equipped vehicle, so it retards my timing automatically to account for detonation. Basically you have to retard your timing enough to prevent detonation, if you don't have a problem with detonation, there is no reason to retard your timing. Retarding your timing unnecessarily will only kill hp. Ignition timing is measured BTDC.

[integra818]

Thanks man. Last question...I heard that leaving your bottle under the sun can raise the bottle temps high and make a 50 shot seem like it's more powerful. Altough I realize this is'nt a good thing (if you want bigger shot, just change the jet right?) but will having the bottle IN the dash, behind the firewall heat up the bottle?

EDIT: what I meant was, will it heat up the bottle enough that it won't be a good idea putting it there?

[Sluttypatton]

That depends on how hot the particular area you are thinking of gets. In my opinion I would just put the bottle in the trunk. The trunk is the best place; its out of the sun, relatively cool, and isolated from the cabin. Personally, I would not want the highly pressurised bottle anywhere near me in the event of a bad crash. The trunk is the safest place to put the bottle, and if you get the remote bottle opener, you can open it without moving.
Another good thing to have is a bottle warmer because as your bottle becomes empty, the pressure will drop. This means as your bottle becomes empty, flow will become reduced due to decreased pressure. The bottle warmer helps keep the flow constant regardless of the amount of nitrous left in the bottle, by heating the bottle to maintain pressure.

To find out if it is a bad idea, measure the temperature where you want to place the bottle when the vehicle is fully warmed up. If the temperature is much higher than the ambient temperature in the trunk, you may want to reconsider it.

[2turboimports]

Originally Posted by integra818

2. Rev limiter, to prevent nitrous going into your engine in over-rev conditions

3. ignition box, altough I have no idea why.

4. a good head gasket

5. 91 octane or higher gas

I appreciate you teaching me all this stuff. If you're getting annoyed by this, you can ignore my questions and I WILL NOT take offense to it.

2) i believe when they say rev limiter they mean changing the limit style. Usually it's a fuel cut when you hit the limiter. you don't want that. if you hit the limiter on spray and all the sudden the fuel stops, then when the revs drop low enough for the spark to ignite, you're going to lean way the hell out.

3) a good ignition system, like the MSD will have 1 of 2 things, or hopefully both. that's a spark advance/retard knob and a spark cutout rev limiter. The advance/retard knob is handy since you can mount it in the cabin and since you won't need to be moving the distributor to change advance it'll be of higher accuracy.

4)i don't think you'll need to be getting a stronger headgasket for a 50 shot. You could probably run up to low 100 shot with the stock head gasket on most cars...however anyhting can break at any moment, so it's always good to be prepared.

fwiw, i had a tec-ii ecu, which is ultimately bad ass as far as standalones go. It had a general purpose output that would activate either boost controller or solenoid for nitrous at chosen presets. The newer Tec-3 model has i beleive 3 GPO's so you can do a 2 step setup and then have a 3rd for whatever. hope this helps some.

[GTR2b]

Some good points brought up about Nitrous but there was also some other things that I thought I should bring up. I've been installing and using Nitrous for quite some time now. About 14 years and I will say that things have changed quite a bit since then but this is the Golden Rule of NO2.

- ALWAYS install an arming switch in line with the power to your button.

- ALWAYS make sure you have adequate fuel delivery to avoid a lean condition under spray

- NEVER spray more than 100 extra hp to a stock engine.

- NEVER, NEVER, EVER activate your spray when the engine in not under maximum load. (ie, accelerating under traction).

Your buddy with the Civic most likely killed his engine by hitting the boost when doing a burnout. There's little load on the engine one the wheels started spinning and most all horror stories about NO2 happen when people do that. Melten pistons, killed head gaskets, melted plugs and burnt valves, guides, stuff like that.

I would personally talk to your a sales rep for NOS or NX. They usually do a pretty good job if determining that your car can handle their kits and what kit is best for you. Just be honest with them when you talk to them.

Cheers!