Car hesitaiting when on the bottle?

[pgriffith]

Car has been running really good off the bottle. But when I spray the car hesitates then goes real fast then stops then goes real fast again. I dont know if that makes any sense to you but its not what it used to be. Could this be caused by my large plug gap .060? They are NGK tr6 plugs but with stock gap. What could be causing this? I sprayed a few days before today and it felt AWSOME. Now it feels faster than NA but not what it used to be? It comes in spurts. 4k rpm it feels good then 4500 it cuts out a little bit then picks up again at 5k. Kinda like that. But not always at the same RPM's. What could this be?

[slacker69]

I would regap them to 45 like i did and so u have a purge before i got my purge mine did ythat because of air in the lines

[mike malloy]

i'm thinknig too much backpressure which is causing your car to chug. mine did the same thing till i opened my cut-out

[pgriffith]

I am running the stock exhaust with a flowmaster rear section. The rear section includes a flowmaster muffler with 2.5 inch tail pipes on each side and nice tips. Is that too restrictive? How should I open it up?

[slacker69]

3" i-pipe and over axel with a high flow cat

[mike malloy]

yea for nitrous that is way too restrctive. your getting all that air in and can't get it out fast enough.

[pgriffith]

I am kinda broke due to my heads and cam I just purchased. Would an exhaust cutout flow enough? I am talking about a cheap $30 cutout placed after the cat on the stock 2.25 inch I pipe? Would this work?

[mike malloy]

a cut-out will be fine. i mounted mine in the middle of my i- pipe. it works great and sounds like a mean son of a bitc@h when on the juice. the car really pulls good with open exhaust

[12secondv6]

That sputtering is called a fuel pressure safety switch!!!
You need more fuel!!!!
Gap them at 0.035!!!
I see people here and there chancing it and gapping them stock, why?
You could possible damage your engine.
First regap all the plgs to 0.035 then test it again.
What shot do you have?
Fuel upgrades etc?
Any chance you have any extra guages? Fuel psi, air/fuel ratio etc?
Let me know asap k?

[pgriffith]

<blockquote>quote:</font><hr>Originally posted by 12secondv6:
That sputtering is called a fuel pressure safety switch!!!
You need more fuel!!!!
Gap them at 0.035!!!
I see people here and there chancing it and gapping them stock, why?
You could possible damage your engine.
First regap all the plgs to 0.035 then test it again.
What shot do you have?
Fuel upgrades etc?
Any chance you have any extra guages? Fuel psi, air/fuel ratio etc?
Let me know asap k?<hr></blockquote>

I have no gauges. I have no fuel pressure safety switch. I am running a 75 shot when this happens. I havent yet gapped my plugs to .035 but I havent used it since then. When I run a 50 shot it doesnt do it. And I have no fuel upgrades. I decided to not use the nitrous untill I regap the plugs.

[RiceyRS]

It's not the fpss, my 98 did that too, it runs fine with a 30 jet but when I went to the 68 jet the car did the exact same thing pgriffith's did. I am running NGK TR6's gapped at .038, so it's not the gap. I gonna add a cutout pretty soon to see if that's the problem.

[pgriffith]

I installed new exhaust. 3 inch mandrel bent flowmaster I pipe with 3 inch mandrel bent tailpipes and 20 inch long 3.5inch wide chrome angle cut tips. I havent seen if it fixed the problem.

[12secondv6]

I'm still wondering why you get a hesitation.
I would normally have guessed at a fpss but if you don't have one then it can not be it :D
Um, do you have an air/fuel ratio guage?
Maybe to rich or lean?
Also what gapping do you have the plugs at?
With ngk tr6's they should be at 0.035

[pgriffith]

I had the NGK TR6's gapped at .060, my mechanic is a dumbass and told me thats the gap to use. I have now found that they should be .035 so I am in the process of chaning the plugs. I have 2 of them changed just need to find the time to do the other 4. Also my plugs looked black. It was dry and black all over the plug. Could this be from running rich. When I called tech support @ NX they told me to use jets 41n/24f and thats what I used. But I called them again and they said thats for the LT1. For our cars 75 shot is 41n/22f. So I was running too much fuel. Could that be the hesitation I am feeling?

[mike malloy]

boy o boy. you gotta love nx tech support. different answer everytime.. ok check it out i have been running my nx kit now for a year with zero problems. i know this kit inside and out.


gap your plugs to .035
get a FPSS this is a must___YOU HAVE A WET KIT!!
run the same size jets as the lt1, jet sizes are based on operating fuel pressure not size of motor.. we have the same psi as the lt1. i have been running the same jets for the longest time.
so keep the ones you have in there.
check fuel filter, they is always over look.
now with this new exhaust you juice will hit 3 times harder, i promise ;)