one more try and im taking it off !!!

ok, i have pretty much a stock 94z, just a few boltons. i bought an nx kit with the gen x upgrade from a board member and installed it with a 100shot. when i hit the nitrous it comes out the hole great but when it gets to about 4000 and up rpm's it starts to sputter and falls off. i've checked the plugs (tr6's gapped at .045 with an msd6a) they look fine. it has an msd coil about 1 year or so old and the opti and wires are BRAND new. ive got 43.5 psi at wot. the bottle pressure stays about 950 psi. i've checked both solenoids and there fine.i thought it might be the shark nozzle so i changed it out with a nitrous works plate and its the same way.

I am lost:confused: :confused: if anybody has any ideas please let me know. before i just blow the whole damn thing up.

have you tried useing a bottle heater. the pressure should be at least 1000-1100 psi. also are you sure your getting enough fuel? i had sputtering problems before i got a heater. i think that may help you. good luck

i have a bottle heater,it keeps it between 950 and 1150 (nx) i have not checked the fuel pressure while actually hitting the nitrous but i do have a 255lph racetronix fuel pump comming this week. i did check the fuel presure while it was in neutral and it pulled 43.5 at wot but like i say thats without a load or hitting the nitrous(which is a wet kit by the way)

Hey Ive a question for you is it only spurting on a Nitrous run. Or all the time your gunning it above 4000 rpms without Nitrous?

well it had a sputter all the time but i fixed that with the new opti. now it runs great on just the motor. it only sputters on the nitrous, thats why im so confused.

Have you tried reducing your spark plug gap more, sounds like your nitrous is putting out the spark. Thats coming from someone who is only going on what they have heard. I'm by far no expert!

Originally posted by Like My Taillights?
Have you tried reducing your spark plug gap more, sounds like your nitrous is putting out the spark. Thats coming from someone who is only going on what they have heard. I'm by far no expert!

Thats a good ideal.....go with .038-.040. Put that new pump in before you give up also. If you have a fuel pressure safty switch you may want to test it....it may be set too high.

Do you have an aftermarket ignition box? If not I'd get one. My car wouldn't rev past 5k on nitrous before I got one. ;)

Originally posted by Derrick Redd
Do you have an aftermarket ignition box? If not I'd get one. My car wouldn't rev past 5k on nitrous before I got one. ;)


as in what? im running an msd 6a but thats it.


gb95zconv--ive got the gap set at .045 with the msd i dont think thats the problem but i guess it might be.

sorry to go off topic, but if you want to sell it, i'm willing to buy it...thanks :)

Deffinetly shorten the gap .38 -.40 . I'd almost bet my car on it.

Originally posted by 94droptopz
as in what? im running an msd 6a but thats it.


gb95zconv--ive got the gap set at .045 with the msd i dont think thats the problem but i guess it might be.

The 6a should be fine.

Ild still drop the gap to .040 max.....That said I belive your problem is fuel related....check the fuel pressure while you spray.

Originally posted by 94droptopz
as in what? im running an msd 6a but thats it.


gb95zconv--ive got the gap set at .045 with the msd i dont think thats the problem but i guess it might be.
Yes, that is what I meant. I'm running a MSD 6A with Autolite 103's @ .040 gap without any problems. 150-175 shot NX. Hope you get things straight. :)

i run at .036 gap and it is what you should do and if that doesnt work jack the fuel pressure up to 50 psi with the vaccum line off at idle and that might help

i can understand running at .036 if your not running an msd but do you really think you should have to with an msd? im going to drop it from .045 to .040 but thats the lowest i've seen people run them with the msd.

we use .036 on a 6AL and it is fine

but you need to make sure that your fuel pressure is at 40-45 psi at idle with the vacuum line on and have it a 53-55 psi at idle with the vacuum line off

also do you have the fuel pump installed yet? cuz your stock one wont be able to handle the extra fuel needed if it has wear on it

no im still waiting on the fuel pump to get here. the stock one has about 105,000 miles on it so im really hoping thats the problem. when i checked the fuel pressure it had about 38 at idle and 43.5 at WOT. is that not about right? thanks for all the help guys
Rob

Originally posted by 94z'sson
but you need to make sure that your fuel pressure is at 40-45 psi at idle with the vacuum line on and have it a 53-55 psi at idle with the vacuum line off
Uhhh, stock fuel pressure w/ the vaccum line off is supposed to be 43.5psi.

what is it supposed to be with the vacume line on at idle? mine was about 38 or so at idle with all lines attached,is that about right? i never took a vacume line off. why would you do that?is there a point unless your gonna run the car with the line off? just wondering. thanks guys
Rob

I run my plug gap at .035 with a digital 6 msd. Your fuel pressure seems fine at idle with the line on. when taking it off, should climb up to around 42/46 at idle.

i'm running 0.038 tr6's with a accel 300+ digital, no probs here either............

Did u check the coil???

well im still waiting on racetronix to get me my pump here. damn its been 2 weeks now. o h well. i'll let yall know as soon as i do.

FWIW, taking the line off at idle simply simulates WOT, so you can check your idle and WOT FP levels without moving the car. But of course it won't actually take engine demands on the pump at WOT into account...