Nitrous users...Have a small problem

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Stangfreak95 said:
I almost went for a Zex in the beginning. But decided to go with NX after researching. I dont think I went wrong...I called NX and the "tech" guy didnt say much. Actually he didnt know too much...

And you still think you made the right choice?? :D Just kidding.

Hey it's a shot in the dark but I went to video tape a dyno tune and the car was on a 150 shot NX. The car would buck on the dyno. They couldn't figure it out until I caught it on video - the nitrous line was leaking when the car went to WOT. This caused the car to go rich-lean-rich-lean really quick causing the bucking.
 
I am sure you checked this but make sure that you have the correct jets in the correct spots. I had this issue with my compucar nitrous kit. Stupid me put the fuel jets in the nitrous side and the nitrous in the fuel side. This caused the car to thrown in a lot of fuel and a little nitrous and the car done something similar to what you described. Your fuel system is not going to matter all that much. The nitrous kit is supplying it's own fuel so the injectors and pump are not going to be the cause.
 
Yes I've checked every connection yesterday. Made sure all the IN's and OUT's were at the right place on the selonoids. Eveything is perfect. And yes I also had the correct jets in there.

Here's what I've been asked to do to test the system and to see what the fuel pressure looks like during a 100shot spray:

*original post from a Corral user*
what i did to test out my system to make sure it was spraying enough fuel was pull off the intake tube and stick the nozzle into a plastic zip lock bag. once that is in the bag go ahead and have a buddy start your car. pull of the vacuum from the regulator so that it simulates wot pressure. rev the car up to say 3,500 rpm and then push the wot switch and make sure the fuel solenoid is spraying. when you do this test you can see what psi the solenoid is drawing from your fuel rail. for a 100 shot it should be about 3 psi that the solenoid causes the pressure to drop.


I just did this an hour ago. So I had a buddy to help. I had 38psi vacuum on that I disconnected the vacuum from to get me to 42-43psi vacuum off, to simulate WOT. Blocked the vacuum that was plugging in the afpr. I had removed the nozzle and put it in a ziplock bag like I was instructed to. All this operation was done by bypassing the fuel pressure safety switch and the window switch so the only thing activating the system is the actual WOT switch. So the car is running at idle at 42-43psi vacuum off. I make my friend tap the wot switch for 1 second, without pressing on the gas pedal. The fuel pressure stayed exactly the same (..if it moved its like .5psi or so) and the fuel was spraying very good in the bag. The nozzle is not "blocked" thats for sure. Then we tried it with him revving to 3500rpm and tapping the wot switch. Same results. The pressure remains where it's at. So I'm assuming my fuel system is top notch. Dont think I have any problems with it, according to this experience. From what I see I shouldnt even raise the pressure from my regular N/A driving to my nitrous driving since it's that stable and that I'm already running rich from the start. I'm thinking the big "bug" I experienced the other night was due to way too much gas in the intake/engine, or still that possibility of a bad fuel safety pressure switch.

What do you think of this now ?
 
Even if I did the test a couple days ago, I still had a feeling that I should of tried it a bit differently. Just a 1second tap on the WOT switch doesnt do much, or might not do much on a fuel system. I wanted to try it longer to really make sure, so I called my friend and we tried it again.

We did it twice like the other day. Once at idle, and once at 3000-4000rpm. But this time we were holding the WOT switch for a good 5 seconds. :D The pressure isnt moving at all to my surprise, and IF, it is again by .5psi or so. Very surprise to see how much fuel is taken with the 100jets. Now I'm very confident in the fuel system and just cant wait to go and try it again. But it keeps raining over here, it's not even funny, and I'm getting pretty damn pissed off about it. :bang:
 
so is there no power gain here? have you run it again and "kept your foot in it"? it kinda sounds like your're nitous to fuel ratio is way off. does the car cut out or bog? are you sure the system is even spraying the juice?
 
rocketcarx said:
so is there no power gain here? have you run it again and "kept your foot in it"? it kinda sounds like your're nitous to fuel ratio is way off. does the car cut out or bog? are you sure the system is even spraying the juice?

Absolutely ALL the components are fonctioning properly except maybe the fsps. Thats the only thing I'm not 100% sure of. I'll know as soon as it is dry outside. I'm thinking it was just way too much fuel when I tried it but I'll see. I know the selonoids work, I know it sprays nitrous and gas. Should work next time :nice:
 
Update

Well I just went back again to try the system. This time I lowered the fuel pressure to 40psi vacuum off. All my safety components are hooked up. I go on a dead road to try it. I'm in 3rd, and when I hit the 3000rpm point, another big "bug" happen but I leave the throttle at WOT and another big "bug" happens so I let go. I was disappointed but at least I knew what I had to do. Since I didnt have the wires to bypass the fuel safety pressure switch, I had to adjust it to the minimum adjustement which would propably be something like 15-20psi I think.

I go at it again in 3rd gear in maybe 55mph, and hit 3000rpm and it worked ! :nice: It was a good kick but less that I expected. I do understand that I was already at that speed and that the tuning of the system is not done. Might still be too rich, I'll have to find that out. So at least I know it works.

Then I wanna try it in 2nd gear. I know I have really cheap tires but I wanna do it anyway. I do it first N/A to see if I'm breaking loose at that rpm. I dont so its all good. I'll be able to see a good difference if I do. So I armed the kit and here I go. 2nd gear, 2400rpm I hammer it. The 3000rpm mark was unbeleivable. The tires broke so loose I've never seen this before and were 100% NOT hooking. Now I need to bring this to the track and dump the clutch at 5000rpm with the nitrous ON. Should be a fun ride :nice:

So that fsps is definately the problem and I'll bypass it tomorrow.

Thanks guys.