Any nitrous users out there know the fuel and nitrous jetting for a 50 shot? I've decided to start at 50, seems to be the safest route for a 1st time. I'll have the regulator set rich and the timing backed off -1 degree from STANDARD. All the drag race guys I know (pro stock, top fuel), said it wouldn't even begin to give me problems with such a small metering. I've decided against the fuel pressure safety switch, simply because I think it not necessary (brand new Carter pump in place). Even with a full dump off the fuel rail it maintains 42 psi. I should be able to get my fuel directly off the test bung (correct me if I am wrong..). Nitrous and fuel lines from the solenoids will be of brake line (1/8"). I am going for a "hard line" plumbing for cost and safety. Stainless braided line is highly overpriced even with a corporate discount...However, the line from the bottle will be the good stuff (it was free). I'll keep you folks posted (If I'm lucky I'll beat AM91's time... )

 

i would advise FOR the fuel pressure saftey switch.

like every other guy with "holy" pistons... they thought their fuel pump was fine too.

why chance the motor when insurance is so cheap and easy?

 

I wouldn't trust that schrader valve to flow more than 20hp worth of fuel. This is not based on any scientific test, just the mere fact that in the end it *is* a schrader valve. I wouldn't chance it, 'bout as much as I wouldn't chance the lack of a fuel pressure switch. You're really looking for an excuse to go find another 3.4, aren't ya...

 

You wanna give me a fuel pressure switch? They aren't cheap to me . Where the hell am I supposed to put it? There aren't exactly many options on these motors. It'll be hard enough getting the fuel to the solenoid (seeing how I can't get it from th rail...) Does Anyone who DOES spray their motor have any suggestions??? I suppose I could machine a fuel bar to go this side of the fuel filter... of course, that will cost quite a bit. As far as the motor goes, installing it was cheaper than installing hedders, and cheaper than nitrous...If I blow it (IF, It won't happen), I'll just get another and this time around I'll build the SOB to make some power.

 

a simple Hobb's Type switch is under $20

goto the hardware store and get a threaded tee block.. then put it between the 'noid and where you're tapping your fuel off from.

since i do spray some of my motors, your welcome for my suggestion.

 

And if you can't afford that little hobbs switch, I'm seriously concerned about what you're doing for the RPM window switch...

As far as feeding everything, tee off from the supply line next to the AC compressor.

 

Ain't no rpm window switch, when I hit 2nd gear at 3500 rpm, button goes down. Thannx for the suggestion about going off the main supply line, don't know why I didn't think of that. What is this "hobbs switch"? The system will have a main arming switch, WOT switch and "tha button".

 

Throw a 75 or 125 shot on it, you really won't feel much doing a 50 shot if anything at all. I think the 3.4 guys safely go with the 125 using the stock bottom end. As far as jets, sorry I have no clue.

 

do i hear a KABOOM coming? Jk, let us know how it works out.

 

Gotta have it so I can keep up with the mighty V8 Brobert . I wanted to start small pasky, get used to using it and whatnot. I've heard of 4thgen 3.4 guys spraying 125 into the high 12's:hail: If I can turn anything thats 14.XX I'll be Very satisfied. And is the hobbs switch the disc shaped thing with two poles? Would I put it into the same type of block I'm feeding the solenoid?

 

Its not all its cracked up to be, Not saying the car isnt faster. Its a ish loads faster. But the hard shifts get to be a BIG PITA REAL fast! I used to like just driving around, Now unless im on the highway or a long road i dont like it too much.
Sure its fun when someone pulls next to you and revs their engine
But the rest of the time when you just wanna relax and go for a drive it sucks.!


Good luck with it man, im sure you'll get 14xx outa it.

 

The Slow and the Curious NAWWWWS kit, straight outta hollywood.

I'm retiring from this conversation. Have fun man, good luck, and don't say you weren't warned.

 

well if your kit is new there will be a small peice of paper in a zip lock bag with the jets and will tell you x + y = shot if i remeber next time im at my buddies shop ill look in my kit i have the nx hitman kit waiting to be installed just gotta find a place to put my pump

 

Don't get an attitude Tech! LOL. And No, no fast and the furry assed here. I don't know what a window switch is, I will have a WOT switch (common item on kits, which isn't what I have). In other words, gas will be spraying when the throttle is open and button is down. All of the kits I have seen work this way, no fancy delay box or anything....

 

a window switch is a saftey item that kits should come with, but most dont.


its a electronic device that will turn on (like a switch) when you are above one RPM and below another.

so if you had it set at 3000 and 5500 your nitrous would only come on above 3000 and shut off when the engine goes over 5500. in that RPM "window" it "switches" on


delay boxes and progressive controllers are nice, but unneeded. a window switch however, is a saftey device to prevent the nitrous from coming on too soon.... i wont run nitrous without a fuel switch and a window switch.


im assuming you dont have anything right now besides the basic stuff you said... so if you plan on spraying more later, for cost and saftey and coolness, its hard to beat the nitrous mastermind.

jacobs nitrous mastermind will retard the ignition only when the nitrous is on.. meaning no power loss when daily driving like you would get if you left the timing stock.
it will turn the nitrous on at a set RPM and off at another (window switch)
it will shut the nitrous down if fuel pressure drops (comes with fuel saftey switch)

but heres the really cool thing.. it will let you "feed" the nitrous in in relation to RPM... and it lets you dial it back... so at the turn of a ****, you can run a 50 shot or a 100shot or have it come on at a 20hp shot and ramp up into a 75.. or whatever you want.


but at the very least, get the fuel switch and window switch. if you cant afford them, wait until you can. because if you cant buythem, you cant buy a new motor

 

yeah the fuel cutoff is recommended the window switch is good too but you really dont need it just keeps your from hitting it too early i would do the fuel ive seen guys literally twist a rod or snap it in half and my favorite is melt a piston thats always a neat sight

 

Interesting. Where would I find a window switch that I could use? And can I get the hobbs switch through Summitt? One more, what pressure of switch should I get?

 

msd makes it part #121-8956 $76.99 from jegs itll turn it on and off at whatever rpms you set it at like 3000 (on) 5500 (off) and the fuel pressure safety switch is #741-15606 $35.99 so for a little over $100 you will be protected oh and if you plan on using that in your fbody your gonna need a blow down tube that vents the nos outside the car in case of too much bottle pressure that is $19.99

 

I already have the blow down tube, it's on the bottle. as for the pressure switch, I appreciate it. I dunno about the MSD box, I'll have to see about that, but it isn't a bad price. Will that switch work in MY case (40psi is right I think)?

 

i would call jegs and ask cause the book doesnt say anything about pressure

 

Wow, I'm glad I didn't rely on this board when I was setting up my Nitrous it would have never been finished.

What's your setup? what parts are you using? is it a kit?
Bottom line, call the tech line for whichever company who's parts you're using and they can tell you what jetting you need.

FACT: I'm not running anything except an arming switch and an activation switch, no fancy boxes, no throttle switch, no fuel pressure safety switch, no problems. I put the fuel pump in a couple years ago, I know it works. My fuel supply comes from the schrader valve with the core removed. I'm shooting 75hp now, and I plan to do 125 in the near future. My engine is not exactly new, 150,000 miles roughly, was running on 3 cylinders when I got it, etc... I've got two bottles thru it with no problems.

 

Dang Drew, livin on the edge??? (lotta miles). My boss told me the same thing, all I needed was an arming switch a button and good sense (don't hit the button at -3000rpm). I think I will still use the WOT switch though, along with the fuel press safety. I don't need the window switch, with the auto shifting at 5000 rpm anyway. If I had a 5 spd, I'd get one.

 

I've got a roller cam 305, B&M 700R4, TPI, dual fans, wiring, and all the nonsense to convert over sitting in my garage. I'm not too worried about blowing the 3.1 to hell.

The reason I don't have the fuel pressure switch is simple, I bought my system as parts and the extra $$$ for the switch, plus install just didn't seem worth the trouble. I have a microswitch, and I used it when I had the same setup on my Formula 350, but on the 3.1 there isn't a good place to mount the switch. I had already custom fabricated a mount for my TPI, I didn't want to spend the time to do another. So, a $4 momentary switch from Radio Shack got mounted to the shifter.

Hitting the nitrous at 3000rpm is just a safety precaution, you can hit it earlier, but the lower the rpm the higher the risk that you'll have a backfire and blow the intake ducting to hell. The lowest I've gone on the 3.1 was hitting it at 2500rpm. If my nozzle was threaded into the plenum behind the throttle body, I'd be willing to chance hitting the nitrous at launch. Even if it did backfire (unlikely) there wouldn't be any serious damage. My current setup uses rather long feed lines (4ft) and the fogger is in the duct in front of the bellows, so its more prone to backfires and puddling.

All said my only complaint is the expense of refilling the bottle.

 

So what are you running at the track with the 75 shot? I'd be interested in knowing what size jets for that one too.