NXZ28

iTrader: (45)

Here are some specifics of my kit.

Fast 90/90 with Nitrous express Direct Port
NX Iceman Solenoids (Brand New)
26N / 14F for a 200hp shot
Nitro Dave's throttle activation switch (manual)
BNM Window switch (4 years old)
Nitro Dave's console mount switch panel
Wired according to BNM instructions with 30 amp relay.
New NGK BR7Es gapped at .030"
-8 degrees of timing pulled
100 Octane Unleaded Fuel


I have tried everything I can think of. The kit used to perform flawlessly. Now it is stumbling extremely bad out of the hole. I launch the car and it just pulls out gently like it is spraying only fuel and then it stumbles real bad twice and then finally hits. I have tried different bottles with the same results. It acts like it is not opening up the nitrous solenoid right away. I have the widow switch set at 3200rpm on and 6800rpm off. I ended up replacing both solenoids with brand new ones and it does the same thing. I recently rewired the kit but it ran fine at the end of April. I can't seem to figure this one out. Here are some of my ideas.

1. Wiring
2. BNM Window switch is going out
3. Relay
4. OUT OF IDEAS

brandoz28

iTrader: (3)

make sure you're getting good grounds, and double check that the WOT switch isn't cutting out. any problems down track?

DC Motorsports

Are you losing voltage? Seen many times where alternator starts to take a **** and slowly makes different systems start to act up, espeacially a direct port that pulls alot of amps. Check voltage at idle at battery then go from there. Its a pretty quick and easy starting point at least. Kinda makes scense being that it worked flawlessly before but it starting to act up.

DC Motorsports

Oh and is there a fuel pressure safety switch?

NXZ28

iTrader: (45)

No fuel safety switch. I thought the low voltage was the problem but I just changed the alternator and the battery voltage looks fine. We were purging it through the motor and it would hesitate on the initial hit and then hit fine. My friend even did this after I did my burnout. He opened the hood and purged it through the motor right before I made a pass. Same result. It fell on its face, stuttered twice and then went. He thought it had air in the nitrous lines on the direct port. I tried to tell him that with over 1000psi of pressure, the air is not a problem. The fuel side seems to be working fine. Does the nitrous solenoid take more amps to open than the fuel solenoid? I know it has more pressure on top of the plunger.

DC Motorsports

On some kits the nitrous solenoid pulls way more amps than the fuel. The Nitrous Outlet fuel solenoid pulls roughly 5 amps while the Nitrous Solenoid pulls roughly 27.

I know you said the plugs are new but how many miles or how much nitrous is on them?

Like asked before, any problems down track?

Anyway to log the runs?

NXZ28

iTrader: (45)

The plugs only had about 20 miles on them. It is pretty much a track only car. On the first pass it stumbled, came on, and then layed down around the 400 ft mark. The car usually runs 6.60s @ 105 on the 200 shot. It ended up running a 7.99@93 with a 2.06 60'. It pretty much did the same thing. Ran a 8.06@91 with a 2.04 60'. Then we noticed tha t it was leaking fuel and nitrous out of three lines while we were burping the kit through the motor. I tightened the lines and changed to a full bottle. The next pass it still stumbled and pulled all the way through once it came on. It ran a 7.68@98 with the same 60'. It had the same problem at Pinks all Out in early May. But it would stumble and then run 7.5X@103 in the 1/8th and 11.33@133 in the 1/4. The engine runs fine on just motor. No misses and it does not seem down on power. I think it is mostly spraying fuel. I have no way of logging the runs. Do you think I should just eliminate the window switch, rewire, change the relay, and hook it up to a push button just to see if it fixes the stumble? I am using a 30amp relay for both solenoids. Would too tight of a converter cause it to stumble so bad? It stalls at 2600rpm on the transbrake.

WE TODD DID

iTrader: (2)

How much fuel pressure?

jmill96Z

iTrader: (3)

Did you mess with the jetting at all? Any chance you swapped the jets accidently? Fuel pressure can play a big part in the equation also, like said above.

Do you have a wideband?

What size stall do you have in the TH350? I would ditch the window switch for a run or 2 to see if it clears up.

NXZ28

iTrader: (45)

Around 50-55 PSI

NXZ28

iTrader: (45)

Never changed any of the jetting since Pinks all Out. 26N and 14F. I have ran it that way for years. No wideband. I will try to run it without the window switch and see if it clears it up.

dnkynrbk

iTrader: (34)

Sounds like a ground or your altnator is failing you. I bought a new one and what a difference it made. Check those two things

ShiznityZ28

iTrader: (11)

Do this. Take the window switch out of the equsion. use just the wot and arm switch and spray it off the line ot see if it stumbles. if it does theres something with the lit if it does not its the window switch.

We had an fjo that could not handle 2 dual noid kits. we put a msd old school window switch on and no more problems. we tried everything new truck high amp alt, voltage booster etc.

NXZ28

iTrader: (45)

I just put a new one on it. I will have to check the voltage output on it. I will check all the grounds again also.

NXZ28

iTrader: (45)

Will do. Is a 30 amp relay enough to handle both NX solenoids or should it be a 40 amp?

ShiznityZ28

iTrader: (11)

30 should be fine. How many total noids do you have? if its only 2 it should not be the switch. how old os the nitrous noid? it could be some debree in it or the plunger is bad. anyone got a noid local to you that you could switch it out and see?

NXZ28

iTrader: (45)

I just replaced the nitrous and fuel noids with brand new ones. It did the same thing. I am only running two solenoids.

ShiznityZ28

iTrader: (11)

OK when you purge does the nitrous come out in a good thick plume? have some one help you and have it arm and spray into a bucket threw the actual noid and nozzle. does it look strong? it should want to pull the line out of your hand. did you log A/F?

NXZ28

iTrader: (45)

It is on a direct port so I would have to take the kit off the manifold. At this point I may just do that. I know it looks good through the purge. I even tried different bottles. I don't have a way of monitoring A/F right now. I know I am slacking in the area but I will eventually get a wideband. It was a major feat just to get this car going this year.

When I launch the car I can hear/feel it bogging. Then it stutters really hard twice and then hits. Once it is on, it pulls all the way through the 1/8th and 1/4. I thought it was blowing the spark out on the BR7e's but I just put a brand new set in it gapped at .030"

ShiznityZ28

iTrader: (11)

When iut bogs is it enough to take it out of the rpm window? Is you base tune 28*? The timming is close enough and the fuel is close enough. but if you timming comes out before the nitrous hits it could bog it enough to take it out of the window.

You can just unbolt the intake and lift it up then manually ground the noid to see if the intke flows good.