NOS Kit user's. Doug? Mark? Beth?

[SASHO91]

I'm just trying to figure out what you're trying to say here. Nothing can regulate fuel pressure except vacuum. How can the NOS regulator "push down" on the fuel pressure regulator to increase fuel pressure? Once WOT is achieved, fuel pressure is MAXED no matter what you do. If you have NO fuel line linked to the NOS regulator, you are achieving nothing in reguards to fuel pressure.

On the note you posted about how I have no idea how it works, NOS will not freeze, it will just make the air charge much cooler (going in) than what it is static. If the air temp is cooler, you should see more gain in HP. If you do not "feel" it, maybe you are used to it. I have plenty of good advice. I am sorry I am not in Texas, but I am on a forum 1k miles away from your car, and cannot see/interpret what you are telling me through a forum.

My bad


/thread

James.... again.... this-- http://www.drynitrous.com/3.html is what regulates the fuel pressure while the system is spraying. Anytime else, yes, the fuel pressure is controlled via vacuum.

NOS will freeze whatever it is going through if it changes state(goes through small holes). Which leads me back to my original question about the nitrous regulator and if it should freeze because of the small holes in it, etc...


You know what James... since you have no idea what i'm saying, why not stop posting in my thread? You don't have the same kit as I do(nor is yours really a kit), you don't know what I'm refering to, and you will not read the link I posted. Your'e wasting my time and we're wasting forum bandwidth going back and fourth.

 

[St Louis SHO]

Ok, my bad, you are on my ignore list now. Dude, I was just trying to help.

 

[SASHO91]

It's nothing personal James... it's just that we are not getting anywhere by doing what we are doing.

 

[St Louis SHO]

All I see is:

This message is hidden because SASHO91 is on your ignore list

 

[SHO Dude]

Is the nitrous regulator suppose to freeze up?
For reference... this- http://www.drynitrous.com/3.html

I had to replace the plunger in the first solenoid as it failed, but i'm worried that it did it again.

I do get a bump in performance with the system activated, but it doesn't feel as strong as it did the first time I sprayed it with the new plunger in. Granted that could be just from the temp difference, bottle pressure etc....
I mean, it is easy to verify that the plunger is still good... However, I just figured I'd ask some of the nitrous junkies here first before I go tearing into the system again.

Also, I did call Holley... and the guy said that would be normal, but i'm not too sure he was on the same page as me.

From the design, it sounds like it should freeze (small holes and what-not), but I just wanna make sure of it.

The kit on my '89 was a pro-fogger type with 6 individual nozzles. It had a fuel solenoid and a nitrous solenoid.

The kit on my '96 is a dry kit and uses Cheater solenoids with the regulator between them. I've got 30lb injectors and gassing 150ish hp. In the heat of the Georgia summer, the small solenoids would fail to open if the bottle pressure was higher than 1000psi. Plus, the Small solenoids will only flow so much.

Now, the parts about your regulator freezing tells me that there is a leak internally. My guess is that you're not getting the nitrous pressure to the fuel pressure regulator and getting the bump in fuel pressure. Lean is Mean, but too lean = SHO-Boom. Trust me on this. You'll use the expression, "Pulled like **** in 1st and 2nd!"

I'd look everything over and make sure that the system is working properly. You can install a fuel pressure gauger and remove the nozzle from the intake, then activate the system. When nitrous sprays out the nozzle, watch the fuel pressure. It should jump up a lot. For a 75hp shot, the pressure should go to somewhere around 80psi. The higher the hp shot, the higher the fuel pressure should go.

If the regulator is freezing, my guess is that it's venting nitrous to atmosphere instead of regulating pressure to the FPR.

St. Louis SHO - 'tis far better to be thought of as a fool than to type crap like ^above^ and remove all doubt.

You're what, like 12 years old? I thought there was an age limit on this board.

"You say that I'm ignorant one more time and I won't be your Best Friend anymore"... whoops, that'll proll'y get me put on the Ignore List too. I'm so ashamed.

 

[SASHO91]

Doug, thanks for the response.
I am 99% sure that the fuel pressure is in fact getting bumped. When the system is triggered, my A/F gauge goes richer than normal. However, the pull (and sound) isn't there as it once was. 3rd gear is where I could really feel the nitrous come in as well as hear the motor start to growl.

I'm going to pull the solenoids and the regulator apart today and see what is up. If it comes down to it, i'll replace the regulator with a used one that I have (it's an older model though).

 

[SASHO91]

I'd look everything over and make sure that the system is working properly. You can install a fuel pressure gauger and remove the nozzle from the intake, then activate the system..

Doug, shouldn't you disconnect the line that dumps the nitrous into the manifold as well off of the Tee?

I lost a motor because of that....

 

[SASHO91]

I pulled the solenoids apart as well as the regulator... everything seemed fine. Threw it all back together, and with the nozzle line disconnected as well as the FPR line I activated the system to see what it was doing. Everything looked normal, and I had plenty of nitrous coming out of the second solenoid.

Here is a picture of what is happening....

This was right after a 1-4 gear run (upto 120). The system seems to be working now, I can surely feel and hear when the nitrous comes in. However, it seems like there is a miss while on the bottle. It only happens once, and it's a very fast miss. I can hear it through the exhaust as well.
I pulled the front plugs, and they look fine.

 

[SHO Dude]

My guess is that it's still lean. (you know, because like, don't have a fuel solenoid and stuff)

"Got WBO2?"

 

[drivinhard]

Looks like a leak to me

 

[SASHO91]

Maybe i'll go swap them out then.

 

[Bizzy]

Oh yeah, there's a leak inside that Josh. I have no doubts. Mine did that once and I had to replace it. From what I was told there are rubber seals inside that can be replaced but I never fiddled with doing that. And why they would use rubber seals in it I have no clue. Since I never messed with it I can't say whether or not the guy who told me that is right or not.

 

[SASHO91]

Yeah, after I posted my last reply I went out an swapped the plungers. The o-rings (aka seals) in both were fine, however, the nylon plunger was somewhat damaged on one of the plungers. Swapped them out and ran the car, and the regulator did not freeze up. It seems to be pulling fairly well now.
Thanks for the help.

 

[Bizzy]

Awesome! Sorry I was so late in getting my reply in.

 

[Brett]

Yeah, after I posted my last reply I went out an swapped the plungers. The o-rings (aka seals) in both were fine, however, the nylon plunger was somewhat damaged on one of the plungers. Swapped them out and ran the car, and the regulator did not freeze up. It seems to be pulling fairly well now.
Thanks for the help.

You make it sound like its still not where you want it to be. Is the "miss" you mentioned that you could hear still there?

 

[SASHO91]

Well, I think that when I sprayed the car the other time that bottle pressure was optimal, and all the other variables were in my favor.

I took the car out again, ran it through 3rd and 4th and even into 5th alittle... did'nt even miss a beat the whole run. So I think that the miss was connected with the bad regulator.

Either way, I can tell that the nitrous is there, no doubt about it.

 

[CosmoSHO]

Looks like a leak to me

Definite leakage. Shouldn't be getting the snowball effect.
The SHO fuel system is a "return" design; the fuel pump delivers excess fuel to the rails and the FPR opens/closes based upon intake manifold pressure to maintain the desired fuel pressure at the rails. At idle on the SHO, factory spec is 39 psi at the rail.
The stock regulator is fine for N/A, but you need a more robust FPR for boosted applications.
The Zex kit install involves taking a reference from the intake manifold,but routing an alternate FPR input from the NMU back to the FPR to force the FPR to close down (minimize) fuel return: net result is the desired fuel pressure spike to deliver more fuel through the fuel injectors when nitrous is introduced to the air charge.