Fogger Nozzle Jetting Question

[wrenchbender]

On NOS brand nozzles - is it common to have a big stagger in the jetting? I was helping a friend of mine jet his fogger on his street chevelle which has a pump gas 496. We ended up with 24 fuel & 32 nitrous - 5 # fuel pressure spraying. He uses -6 feedline. I had a nitrous works nozzle system in the mid 90's & I ran bigger fuel jets than nitrous - which I realize diferent brand jets flow different rates.Just wondering what you nitrous veterans have discovered. Thanks.

[Rick M]

That tuneup sounds pretty normal on the NOS fogger. I don't know that i have ever heard of any one using bigger fuel jets on any system. But no matter what anyone says always read your plugs could of just been a difference in fuel systems.

[John_Heard]

If that's not a typo 24F/32N@5psi - You want to be real careful with a tune up like that, on some cars it would be way too lean. I'm not sure how you're getting away with it right now, perhaps the nitrous solenoid is restricting the flow or something.

Some stagger with the fuel jet being smaller is common especially with higher than ~5 psi tune ups but that tune up is a BIG stagger at low pressure. Any change to that system that fixes whatever is going on - like different solenoids, even jets and you had better start back at a baseline tuneup cause something isn't quite right.

[wrenchbender]

That's exactly what I was thinking John. I realize I didn't explain it well in my first post but anything bigger on the fuel side & it goes fuel rich. It even has a pretty good black smoke plume with 24's on the fuel. To me it seemed to be a bit large of a stagger. He's running twin 10# bottles in the trunk with -6 feedline all the way & it is a race style fogger with twin nitrous and fuel solenoids. BUT, it is a used system he bought from one of his racing buddies that supposedly worked well although I never saw it. I have seen nitrous solenoid seats pucker & distort thereby restricting flow but all of his plugs look uniform rich.I just wanted to make sure that NOS nozzles didn't jet funky for some reason. I've played with a lot of plates but only 1 set of fogger nozzles & that was a set of Nitrous Works way back in '94. I had them on a cheap sacrificial 406 & they always worked well. Hey Rick M - I dug back in my log book & I was running 33 nitrous jets with 37 fuel jets @ 6 # fuel pressure! See why I was wondering?! It still sounds like a nitrous restriction doesn't it? Thanks for all the replys!

[John_Heard]

One thing for sure is you have to be careful comparing one systems jetting to anothers if you don't have lbs per hr information on it, not only that some systems are a LOT more efficient than others and will move more liquid nitrous. I'd say your buddy's car has something plugged up somewhere and it sure sounds like it's on the nitrous side.

Sure wouldn't hurt to pull the noids apart and look them over good, if you can't find it then it would probably be a good idea to yank the whole intake off and start doing some flow testing to find where the restriction is at. Does he have filters in the system somewhere? Those can get plugged too.

Note: There were a batch of bad NOS nozzles that came out a few years back, this probably has supposed to have been fixed but it's something to be aware of. It's a problem with leakage between the nitrous and fuel side making the nitrous pressure the fuel system. This doesn't sound like what you're running into, but you might want to read this for reference:

http://texasmeltdowns.com/FOGGER.HTM