SiR831

I'm running a gsr motor, 255lph high psi warlboro fuel pump, NOS direct port system 80 shot. When the nitrous system is armed I'm encountering a pause / hesitation for a split second before the nitrous hits. Notice below that i have the fuel pressure regulator T'd off directly at the end of the fuel rail. While the nitrous solenoid is fed via an inlet port of the fuel pressure regulator. Is it possible that the fuel rail is starving from fuel once the fuel solenoid is activated or opened? Any ideas?

The Original Whitey

Are you purging before you spray? The hesitation could be the air in the lines.

SiR831

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by The Original Whitey &raquo;</TD></TR><TR><TD CLASS="quote">Are you purging before you spray? The hesitation could be the air in the lines.</TD></TR></TABLE>

Yes i do purge, have a bottle heater, and digital 6 plus & msd external coil if it matters. Another member suggested adding an inline fuel pump along with the 255lph hp warlboro fuel pump. Bump for aome ideas

crucian

no need to add an inline fuel pump! I will add more when I get back from school. Im late as hell!

blackmagicCRX

in my opinion the best setup to run is a completely seperate fuel system for the nitrous, that way you won't have the sudden drop in fuel pressure at the rail when nitrous is activated.......goodluck

crucian

I would "T" the fuel solenoid of the top of the fuel filter instead of off the fuel regulator. According to the picture, it looks like the fuel solenoid is taking the fuel after it goes through the regulator.

CiViC SiR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crucian &raquo;</TD></TR><TR><TD CLASS="quote">I would "T" the fuel solenoid of the top of the fuel filter instead of off the fuel regulator. According to the picture, it looks like the fuel solenoid is taking the fuel after it goes through the regulator.</TD></TR></TABLE>
agree
its always better to take the fuel befor the the fuel rail and after the the fuel filter.

cyipher

With that type of reg assuming is an areomotive 13109 the 2 side ports and the "IN" and the bottom is "OUT". Do you run a FPSS?? Also ive heard of people Placeing the FPSS after the fuel solenoid, and wiring the Fpss to control the nitrous solenoid, by doing this fuel pressure has to rise before grounding fuel pressure switch to the nitrous solenoid.

raceACCORDingly

t it before the rail and if its still the same and your ghetto like me just stick a slightly larger fuel jet

RZFD

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crucian &raquo;</TD></TR><TR><TD CLASS="quote">I would "T" the fuel solenoid of the top of the fuel filter instead of off the fuel regulator. According to the picture, it looks like the fuel solenoid is taking the fuel after it goes through the regulator.</TD></TR></TABLE>

FormulaGSR

i T ed off my fuel filter and have NO problems. Thats the way to do. also you can add a FPR in the fuel line to the nozzle to help make small adjustments. I did this to a friends car and its great. Now all we change are the nitrous jets and use the FPR to adjust fuel.

Phase Change Racing

Lets get the basics down. What jets are you running for nitrous/fuel and what fuel/nitrous pressures are you running?

Have you noticed if the hesitation decreases when you don't purge?

A common problem with almost all nitrous systems is proper event timing between the nitrous and fuel. What I mean is the timing of the fuel and nitrous hitting the engine at the same time. Think of the system as a race between the nitrous and the fuel when it is activated. You have fuel at roughly 50psi in pure liquid form vs. Nitrous at roughly 900psi in a gaseous/liquid combination... racing through the same length lines. Pretty easy to see who wins that race. This is one of the reasons I always plumb my systems with the nitrous lines longer than the fuel lines. I have found in my research that ideally you want the nitrous lines to be almost double the length of the fuel lines. If you hook up a narrowband AF gauge you can visually see this happen upon activation. The thing will go DEAD lean when the system activates and bounce back to green.

Instead of replumbing your entire system you can use a digital delay device to delay the activation of the nitrous solenoid a little bit. I'm still researching exactly how much time delay is necessary but .1 seconds should be sufficient as a ballpark guess. The other really nice advantage of this setup is you can use it as traction control for the initial hit by making the system go rich when it activates to soften the "hit".

My $0.02 on the subject...

quickda6

Phase is correct. What you are feeling is more than likely a nasty lean condition for a split second, then it will richen up and stay steady. This has happened on a few direct port kits i have done, until i wised up and started making the nitrous lines longer. The best way is to tune this out, because no matter what the length of the lines is, the juice will always get there first.

TURBOFTW

iTrader: (1)

i have the exact same problem with my car....it hesitates for a slit second and then takes off like a bat out of hell...

SiR831

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Phase Change Racing &raquo;</TD></TR><TR><TD CLASS="quote">Lets get the basics down. What jets are you running for nitrous/fuel and what fuel/nitrous pressures are you running?

Have you noticed if the hesitation decreases when you don't purge?

</TD></TR></TABLE>

Jets are 22 for nitrous and 16 for fuel. I'm using a pressure activated switch for the bottle heater, so nitrous pressure is @ 1150psi. Fuel pressure is at 45-50 psi with the vacuum line connected. And haven't tried running the car without purging.

SiR831

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crucian &raquo;</TD></TR><TR><TD CLASS="quote">I would "T" the fuel solenoid of the top of the fuel filter instead of off the fuel regulator. </TD></TR></TABLE>

Phase, So this wouldn't help at all? Is there any company out there that makes a delay box?

Phase Change Racing

No I don't think the "T" setup is going to change anything for you. No purging will help out a little bit and running a lower bottle pressure will also help a little bit. If you don't purge you can actually "tune" this lean surge out by increasing the length of the feed line. You won't get rid of it completely, but you can cut down the severity of it. Any digital delay device will work but to do it right you need one that will delay in .01 increments. Do a search for "time delay relays" and you should find what you are after. There are pretty affordable analog units out there, or you can step up to a digital unit for a touch under $100. I'm currently working on putting together a delay kit to offer as a traction control/ event timer system but its like my nitrous/propane system... a ways off still.


Modified by Phase Change Racing at 7:37 AM 4/21/2005

whatVTEC

anyone have any experience with those NOS programmable controller or Jacobs mastermind?

Phase Change Racing

The Jacobs unit is pure garbage. The NOS unit is just a tiny bit better and does kinda sorta work. Take the lean surge I mentioned above and multiply it by 50x a second, that is what you get with a progressive controller. The idea of a progressive controller is awsome, but current nitrous systems are just not built to meter nitrous and fuel like the progressive units try to force them to do.

cyipher

http://www.speedshop.org/store...t=107

These guys are great and very helpful too.

Phase Change Racing

I love Dyno-Tune. I get a better deal on their bottle heaters paying retail than what I can get them from my whosalers for. A number of good people over there at Dyno Tune.

crucian

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SiR831 &raquo;</TD></TR><TR><TD CLASS="quote">

Phase, So this wouldn't help at all? Is there any company out there that makes a delay box? </TD></TR></TABLE>

Phase is right. But I would still do the easiest thing first. It never hurts to use the process of elimination. I would still try to "T" it before the regulator at the filter. Do that and see what happens, then move on from there.

jeffchaisi

your problem is your digital 6 retart timing while u squeeze nitrous go look at your digital 6 and check how much timing does it pull when u use nitrous. usually 1 degree of timing retard is enough.

whatVTEC

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jeffchaisi &raquo;</TD></TR><TR><TD CLASS="quote">your problem is your digital 6 retart timing while u squeeze nitrous go look at your digital 6 and check how much timing does it pull when u use nitrous. usually 1 degree of timing retard is enough.</TD></TR></TABLE>

I'm running Digital 6 retard and mine doesn't have any kind of delay

Phase Change Racing

Timing issues shouldn't cause a bog like that unless it is being retarded to something rediculous like 0 total or something. Or the obvious flip side, too far advanced and she detonates. But neither condition goes away after a split second.