Nitrous users...Have a small problem

Stangfreak95

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Nov 4, 2002
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In your sister. If none, your mom
I went to try the juice 2 nights ago without knowing which fuel psi I should have. I adjusted it so I had 46psi vacuum off, instead of my normal 42psi. I had the bottle heater on and pressure was at 1000-1050psi or so. My plugs were gapped at .035 and my timing was retard as well. Everything was correctly set up. I had the 100jets on there. It's a NX wetkit. I have all the gadgets for it. Purge, fsps, window switch (3000-6000rpm), wot. So I'm in 3rd gear slowly accelerating and I hammer it. I'm in the 23xx rpm and just waiting to hit the 3000 mark for the system to activate. When it hits it, something happens...A BIG "engine buck" of some kind so I let if off right away, not knowing what was happening. At least I know the WOT and msd window switch work fine. I know the wiring is dead on. Just not sure what happened...

1) My Fuel safety pressure switch is set up at 35psi. I've heard that it shuts down sometimes when it comes to close to that point. Could it be this that made the bucking ?

2) I have the 255lph high pressure on there so I know I have enough fuel thats gonna be pumped in... Also have the 24pds injectors. Could "hot" fuel make the engine buck ? By that I mean this. The fuel is taken from the fuel rail to the fuel selenoid. I'm not sure if this fuel is "recirculating" or if it's just there in the line, warming up waiting to be entered in the fuel selenoid...What do you think ?

Thanks
Mario
 
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What kind of sound did it make? Did it sound like detonation?

Check your spark plugs, all of them. Make sure they look okay. Do this every time you run the juice the first few times.

Hmmmm....not to sound like too much of an ass....but have you ever ridden in a car using nitrous before? Perhaps the buck you felt was the nitrous doing it's job? :lol:

Hopefully someone else will respond here. Generally, nitrous problems will lead to recognizable extreme detonation.
 
Swarzkopf said:
What kind of sound did it make? Did it sound like detonation?

Check your spark plugs, all of them. Make sure they look okay. Do this every time you run the juice the first few times.

Hmmmm....not to sound like too much of an ass....but have you ever ridden in a car using nitrous before? Perhaps the buck you felt was the nitrous doing it's job? :lol:

Hopefully someone else will respond here. Generally, nitrous problems will lead to recognizable extreme detonation.


:stupid: He knows what he is talking about. Its prolly just the nitrious tring to work. When nitrious goes wrong it is all most always leads to something horrible. You will usually have a detonation. So just go out and try it again and stay in it. If you hear any detonation get off but you should be fine on that case.One more thing i would check would be is if your ignition is hot enough. you might need to buy a new coil, cap and rotor wires and a module. If it does that again that is where i would start with your prob Let me know how it goes. If you have any other ?'s i would be glad to help you out man just pm me
 
IM_FASTER_THAN_ said:
:stupid: He knows what he is talking about. Its prolly just the nitrious tring to work. When nitrious goes wrong it is all most always leads to something horrible. You will usually have a detonation. So just go out and try it again and stay in it. If you hear any detonation get off but you should be fine on that case.One more thing i would check would be is if your ignition is hot enough. you might need to buy a new coil, cap and rotor wires and a module. If it does that again that is where i would start with your prob Let me know how it goes. If you have any other ?'s i would be glad to help you out man just pm me

I can assure you it is NOT detonation. I know exactly what detonation is trust me. What is happening is like the car just been cut of fuel or flooded with fuel or whatever. I dont have a visual fuel pressure gauge so I have no clue. If you would see what it does, it would not make you want to keep the pedal to the floor. I dont think it's the nitrous trying to work (more that it tried to work..). That fuel pressure safety switch might be the problem. Did what I wrote in the original post make any sense regarding that possible issue ?

Thanks
 
Got me at a loss, Stangfreak95. Since you are positive it is not detonation, here is my suggestion:

Disconnect the nitrous bottle. Make sure there is no nitrous left in the lines by taking it for a run and hitting engaging the system with the bottle disconnected.

Come back home. Park your car. Hook up a fuel pressure gauge to your schraeder valve or to your fuel pressure regulator if you have one that accepts a gauge. Now idle your car and have a friend arm the system. I assume your system is activated by a WOT micro-switch. Have your friend activate the nitrous for a second while you watch the pressure gauge. I'm not sure how you system works, but on my dry kit the fuel pressure will spike a few PSI. If you get a spike that is very drastic, you know what the problem is. If you lose lots of pressure, again, you know what the problem is. Your wet kit may cause you to lose a few PSI as it uses some of the fuel. More than a few PSI gone should be cause for concern.

I would then assume that the solenoids are incorrectly assembled?

And perhaps someone with an NX wet kit would like to pipe up here? I'm trying to help, but I'm sure that my Zex dry kit is WAAAAY different than your wet kit.

Not to hijack........ but what does detonation sound/feel like?

Mild detonation sounds like nails rattling in a can...a "pinging" sound. Heavy detonation may sound like this for a moment before you lose power and possible damage your engine.

And how can you tell by the plugs if you are? What will the plugs look like on a safe shot?

Do you have a Hayne's manual for your car? On the back of it they have illustrations of plugs that explain how to read them. On nitrous, your plugs should either look "normal" or slightly "glazed" is okay usually. Glazed plugs indicate that the combustion chamber temperature has dramatically increased rapidly, which is what nitrous does and is why you use colder plugs. If the plugs show signs of a lean burn or detonation, something is wrong.
 
Swarzkopf, you seem to know a decent amount with the bottle? Thanks for the info on my question! I do have a manual and i'll go by that for referance when i'm all plumbed and ready to go. I noticed that you mentioned something to Stangfreak95 about the solenoids being incorrectly assembled? Do you mean he MIGHT of hooked the lines up backward's? Meaning that he has the in in the out ports and visea versa? BTW all i have left to do is fab up my mounting bracket's for the solenoids and get them hooked up, as well as the heater hooked up install the plate for the system, damn i cant wait!!! I'll start off with the 75 shot then go to the 125-150 for the final one. Once again thaks! peace


john :p
 
SMOKEDYA, while I feel comfortable talking about nitrous, the only system I REALLY feel confident discussing is the Zex kit that I run. I'm really shooting in the dark with this problems Stangfreak is experiencing, but since no one else is stepping up I figure I'll try to help out if I can.

I noticed that you mentioned something to Stangfreak95 about the solenoids being incorrectly assembled? Do you mean he MIGHT of hooked the lines up backward's? Meaning that he has the in in the out ports and visea versa?

That's what I was thinking, but like I said, I can't say for sure since his system is so different from mine.

BTW all i have left to do is fab up my mounting bracket's for the solenoids and get and get them hooked up as well as the heater hooked up install the plate for the system, damn i cant wait!!! I'll start off with the 75 shot then go to the 125-150 for the final one. Once again thaks! peace

Congratulations. Starting with the 75 is a good idea and is what I did.

Make a full pass on the 75 shot and check all of your plugs. Do this the first few times, and repeat it everytime you bump up the shot size. If you appear to be running lean, increase fuel pressure to compensate. Get off the nitrous right away if you feel or hear any sign of detonation. Good luck.
 
Swarzkopf said:
Got me at a loss, Stangfreak95. Since you are positive it is not detonation, here is my suggestion:

Disconnect the nitrous bottle. Make sure there is no nitrous left in the lines by taking it for a run and hitting engaging the system with the bottle disconnected.

Come back home. Park your car. Hook up a fuel pressure gauge to your schraeder valve or to your fuel pressure regulator if you have one that accepts a gauge. Now idle your car and have a friend arm the system. I assume your system is activated by a WOT micro-switch. Have your friend activate the nitrous for a second while you watch the pressure gauge. I'm not sure how you system works, but on my dry kit the fuel pressure will spike a few PSI. If you get a spike that is very drastic, you know what the problem is. If you lose lots of pressure, again, you know what the problem is. Your wet kit may cause you to lose a few PSI as it uses some of the fuel. More than a few PSI gone should be cause for concern.

I would then assume that the solenoids are incorrectly assembled?

I appreciate your help. I do have a fuel pressure gauge bolted on the fuel rail sort of. I dont have one in the car to see really whats happening during driving. Isnt it not dangerous to spray the car on while on neutral/parked ?

My setup works with the WOT switch is placed under the gas pedal. Also has the window switch and the fuel saf. pres.switch. So basicly I have 3 "safety" equipements if I may say. 2 of the 3 I'm positive they work. It's just that fsps that I have doubts in. I actually dont need a friend to try it. I can tape the wot switch together so it is "clicked" constantly and just give it some throttle at the tb itself til I hit 3000rpm. Just not sure if it is safe. I want to back off the settings in the fsps also to 30psi lets say instead of 35psi.

And about the assembly, I'm 99% sure I have it alright. I'll double-check everything today. The wiring I know is perfect.
 
Isnt it not dangerous to spray the car on while on neutral/parked ?

You don't want to spray on a motor that isn't under load. You know how much faster your engine revs in neutral; well, your engine also revs much faster when the nitrous is flowing. I wouldn't spray in neutral because you would hit rev limiter in less then a second and probably bounce it once or twice before letting off.

I want to back off the settings in the fsps also to 30psi lets say instead of 35psi.

You may want to check the fuel pressure as it sits the way we discussed before you do this. More fuel pressure is usually a good thing when your dealing with nitrous.

Good luck!
 
Well I checked a few things...All the connections are perfect. Everything is on the "right" side. So I didnt screw up on the install. I already know that the wiring is ok aslo, as I said before. Same for the window switch. I dont even know if I ever checked the solenoids "clicking" but I just did and both of them are doing their job. I also clearly hear it spray in the cai. All this done with the key to "on" position.

Now I wanna test it to check fuel pressure raise/drop. I'll be doing this by bypassing the window switch and fuel safety pressure switch. So if I understood correctly, you want me to start the car, let it idle, arm the system, and give a little tap on the wot switch to activate it, without giving it additional gas ?

Thanks
Mario
 
Swarzkopf said:
Damn man....44 PSI should not flood your engine.

It would be really nice if someone with the same kit as you would pipe up...

It's weird. I can adjust the afpr to 44 psi and the stang will idle find. But when I clicked, it went to that. Maybe because this is all done on idle. Maybe if I rev the car a little bit and then tap the wot, the car will be ok. :shrug:

Stang is actually for sale but I would actually like to "feel" nitrous and at least make the system work properly before I get rid of it.
 
Perhaps the extra fuel coming through both the injectors AND the manifold is causing the engine to go really rich?

Maybe try turning your FPR down to 32-33 and try it again?

Hell, at this point just sell the damn NX wet kit and buy yourself a Zex system. :lol:
 
Swarzkopf said:
Perhaps the extra fuel coming through both the injectors AND the manifold is causing the engine to go really rich?

Maybe try turning your FPR down to 32-33 and try it again?

Hell, at this point just sell the damn NX wet kit and buy yourself a Zex system. :lol:

I almost went for a Zex in the beginning. But decided to go with NX after researching. I dont think I went wrong. I'm sure it's something really simple. Both kits are great and make great power.

I called NX and the "tech" guy didnt say much. Actually he didnt know too much. But did mention that the kits are designed to work on stock fuel systems so since I had aftermarket injectors, higher fuel pressure, etc, that I might be running too rich, making the system "bug". Makes sense. He says the fsps is not the problem.

I will try it again with the fuel pressure down and if that still doesnt work, I'll bypass the fsps to see what happens.

I really appreciate your help :)