i plan to spray 75 hp on my max. all i need to know is what size jet do i need to use?? oh yeah, what should the fuel pressure be for a 75 shot??

thanx guys!!

-Jason

 

Depends on the system you plan on using since the jets are not interchangeable, but more than likely a .036 jet with a .042 bypass. As for your pressure, when under WOT and N2O your FP should be around 60 psi.

 

as for jet size...if you're using the NOS kit, you don't have a 75 shot...you do have a 70 though, it's a .036 jet....and you should get 70-72psi of fuel pressure....60 psi would be a little lean on a 50-shot.

 

The only way he will get 72 psi is probably an adjustable FPR. I'm running 60+ psi under WOT with an aftermarket FP but stock regulator.

 

The ability to run a constant 72psi while spraying highly depends on the condition of your fuel pump. It does not depend on the FPR, per se. A FPR can only "regulate" up to the limit of your fuel pump. If your fuel pump can only handle a max of 60psi, there is no way an adj. FPR will allow you to run at 70psi. Some people here with stock fuel pump might be able to run 72 psi; however for me, my stock fuel pump (80K miles) couldn't even hold a steady 50 psi, so I swapped in a Walbro and no more probs.

On a side note, with my adj. FPR, I had to adjust idle to 27psi in order to get WOT to 41psi (normal is 43). I intentionally leaned it out a bit at WOT to see if I could gain some HP. I think it works since my AF meter shows I'm running leaner at WOT. Also, I don't know if gas mileage can be attributed to it, but on the past two tanks of gas, I've been getting better gas mileage than before (same daily routine, same driving habits)..

 

i plan to get an AEM universal fpr, and use stock fuel pump. i do have an NOS kit; sorry, i forgot to tell you that...

anyway, what's the .042 bypass?? i'm gonna run a dry shot.

 

In the nitrous T-fitting, there is a jet, what they are saying is to use the .042 jet size in the fitting, though this will vary by car and will depend on what fuel pressure you are running at.

 

???? i still don't get it...

i am going from the bottle to a tee between 2 soleniods, one for the nozzle to the intake, and one to a purge valve. from the tee, i'm going to the soleniod, and then to the nozzle. the jet goes in end of the hose that hooks to the nozzle. i don't have anywhere else to put a jet!! i don't thnk i'm gonna put one in for the purge valve, just the one for the nozzle.

once again, i'm running a dry shot-NO GAS INJECTED. this is the way to spray a maxima, from what i hear, to prevent puddling in the intake runners.

 

We understand you are running a dry shot. You have to trust us on this, there is a jet called the bypass jet located at the "tee" fitting that is going to be connected to your stock FR. The combination of BOTH jets is going to determine the amount of "shot" you have and also going to help you on the mixture (but not by much). If you have purchased your kit, take it out and look closely at the instructions and you will see what we are talking about.

 

i got a used kit...2 actually. lots of parts lying around... anyway, i have this blue, hex-sided thingy with what appears to be an inlet and an outlet. is this what i'm s'posed to connect to the fuel regulator? does this thing raise my fuel pressure when i open the soleniods? i'm trying to figure this out in my head, but not real sure.

does anyone have a diagram for this setup??

 

At the other end of the "blue thingy" is going to be connected to a "tee" inside that is going to be located your bypass jet. The blue thing makes your stock FPR bump up the fuel psi for the increased demand once the N2O silenoids are activated. As stated before, the combo of bypass and main jets is what makes the HP rating. What brand of N2O kit do you have? Because some parts are not interchangeable between kits, i.e. jets. The best thing to do if your kit is used and no instructions is take all the parts and lay them out before starting the install to make sure you have all the parts. You don't want to do a half a** install on a N2O kit. Once you have all the parts there, BTW you will have to do a couple of HomeDepot runs for parts that have to be adapted to the max to make the system work properly, then you can see if you to order anything and can be directed to correct place. NOS has a great tech line, it's long distance but once you get through those guys know their stuff. Good luck. Let us know how it turns out.

 

http://www.brian1.net/~chebosto/norcaldyno/jeff_nos.jpg

Here is a picture of my nitrous setup before the addition of the adj. FPR. The blue hex-sided thingy to which you are referring is the nitrous pressure regulator which, as can see from the picture, sits between the solenoids.

See that black hose that comes out of the nitrous pressure regulator? The other end of the hose connects to the center leg of the pressure tee (which is hidden in this pic). The fuel pressure bypass jet sits inside this tee.

From the pressure tee, one of the remaining two ends connects to your intake manifold, the other end connects to your FPR. I hope this helps.

 

lol, it sucks without instructions huh?

 

I have heard it can even with them.

SuDZ

 

thanx, guys. i have a few questions still...calsonic, of the two soleniods in the pic, (from the front of the car) the braided line on the left one comes from the bottle. the nitrous runs into that solenoid and goes into the tee where it is split off and goes into the other solenoid AND the pressure riser. nitrous then flows from the 2nd solenoid to the nozzle. okay, my question is, the black hose that runs from the pressure riser, does it spray nitrous from the riser to the fuel line and the manifold, or does it mix gas in with the nitrous that's spraying into the second soleniod and into the nozzle??

 

No, the nitrous pressure regulator does not spray anything. The only thing that will ever be inside the black hose is air. The only nitrous that ever enters your motor will be from the fan spray nozzle.

 

thanx guys! i just got an instructions from the holley website. i understand how this thing worx now. so, really i won't need an aftermarket fpr with this pressure riser, huh?

calsonic, i wanna talk to you some time about your mods. they look pretty extensive...i'll e mail you tomorrow or something.