Can't boost over 5-6psi PLEASE HELP

Matthew said:
well originally it was a multitude of things...i wasnt trying to be a dick bro, just trying to figure things out from every angle.
I know and I was narrowing it done for you. . .
If at 4 psi, you run fine, you hit partial throttle and don't go lean that means the O2 clamp is working (which you also heard it was clicking, which means the vacuum supply to it is working. . .yes I read this whole damn thread). Also, if it goes rich, that means you are getting extra fuel. Now the ECU isn't doing that on its own, so the FMU must be raising pressure, so it too must be doing its job. Now if those are doing their jobs and you're sure there isn't a vacuum leak (you should pull about 20 in Hg at idle), then by process of elimination it is the pump.

These pumps will not push enough fuel when they get to 90 psi (I believe FM tells you to keep it to 75 psi at 6 pounds of boost and says the fuel system cannot support more than that and they supply an inline pump!). So, you're trying to push 90+ at 5 psi with the crappy Vortech FMU which cannot be adjusted without changing a stupid aluminum disc and ring and blah, blah, blah.

Anyway, as I said, I WAS narrowing it down for you. Your fuel pump doesn't have the balls to push it. And as others have chimed in, theirs didn't either, so don't let this reflect badly on you or your car. :D (You wife shouldn't either). Stay at 4 psi, and get an inline or new pump. Then go higher.

A fuel pressure gauge is good to have since you will be running high fuel pressure, it will at the very least allow you to see when the FMU is or isn't working and such. As for someone running 11 psi with an FMU at 10:1 or so on a stock pump, that is BS plain and simple, take that bastard out and beat him down for being full of @#$%!

Can we call this a night?
 
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1st MP3 in NH said:
That sounds like you had the FMU run backwards so that it was resisting fuel flow. Like I said though I can't help much for an FMU. I just don't have experience with it.

Its not something simple like using the fuel feed line instead of the return line it?
nah im sure its hooked up right...from the stock fpr (shortly thereafter to the right about 6 inches) it runs to the inlet side (fitting with right angle on side of FMU) and it comes out the bottom and goes to the tank or the firewall or whever.
 
Little Beavis said:
Can we call this a night?
no you people must keep working on possible other problems! lol...im going to bed i have to get up in 4 hours, ive got soldiers to train and condition :D

but i feel better knowing the most likely problem...and ill be ordering a pump tommorrow. hopefully that will solve the problem.
 
Little Beavis said:
I know and I was narrowing it done for you. . .
If at 4 psi, you run fine, you hit partial throttle and don't go lean that means the O2 clamp is working (which you also heard it was clicking, which means the vacuum supply to it is working. . .yes I read this whole damn thread). Also, if it goes rich, that means you are getting extra fuel. Now the ECU isn't doing that on its own, so the FMU must be raising pressure, so it too must be doing its job. Now if those are doing their jobs and you're sure there isn't a vacuum leak (you should pull about 20 in Hg at idle), then by process of elimination it is the pump.

These pumps will not push enough fuel when they get to 90 psi (I believe FM tells you to keep it to 75 psi at 6 pounds of boost and says the fuel system cannot support more than that and they supply an inline pump!). So, you're trying to push 90+ at 5 psi with the crappy Vortech FMU which cannot be adjusted without changing a stupid aluminum disc and ring and blah, blah, blah.

Anyway, as I said, I WAS narrowing it down for you. Your fuel pump doesn't have the balls to push it. And as others have chimed in, theirs didn't either, so don't let this reflect badly on you or your car. :D (You wife shouldn't either). Stay at 4 psi, and get an inline or new pump. Then go higher.

A fuel pressure gauge is good to have since you will be running high fuel pressure, it will at the very least allow you to see when the FMU is or isn't working and such. As for someone running 11 psi with an FMU at 10:1 or so on a stock pump, that is BS plain and simple, take that bastard out and beat him down for being full of @#$%!

Can we call this a night?
1)how is a vortech fmu s***? have you ever used it? if not i guess you shouldn't call the product bad.
2)ive ran over 8.5psi(not saying excactly how much) for about 4 months on stock pump with no problems on a vortech fmu..although i would not run 11psi on stock injectors but with an AIC, i would definately run 11-12 psi and not worry about it on STOCK pump(guy that did my turbo kit ran that setup for over a year and car still runs strong)
 
so is it possible that my pump just sucks like craig said? like its only on the lower end of the standardS?
 
i know this is a stupid ass question, but how can i check the damn guage when im boosting. lol. every guage people have talked about on here seem to mount to the fuel rail.
 
mp5jeff said:
1)how is a vortech fmu s***? have you ever used it? if not i guess you shouldn't call the product bad.
2)ive ran over 8.5psi(not saying excactly how much) for about 4 months on stock pump with no problems on a vortech fmu..although i would not run 11psi on stock injectors but with an AIC, i would definately run 11-12 psi and not worry about it on STOCK pump(guy that did my turbo kit ran that setup for over a year and car still runs strong)
Given that a BEGI allows you to adjust the start and the ramp and the Vortech has a set start and can only be "adjusted" by placing in new "calibration" discs and rings I consider it to be a crappy system. Since I talk about the rings and discs, one might be willing to guess that I have used it and learned that it was crap. So I will call it what it is s***! How do you like that? :)
(Note: I could care less.)

Do I sound like a newbie to you?

That is cool that you ran 8.5 psi on the stock pump. What disc did you have in? What fuel pressure were you seeing. I would say you were the lucky in that you had a strong fuel pump. Most of us were not so fortunate!

As for your comment on the AIC. I agree 100%, so no problem there.

I'm sorry if your family works for Vortech and you're trying to defend your sister's honor. I just voiced my opinion. If you'd like, I can edit the post and change it to "less than desirable operation". :D
 
i guess ill be SOL if i get this pump with no luck still...

btw where has everyone bought steel braided fuel line? i cant find any in this bad ass town.
 
lets try to be civil everyone this thread is really helping out and i would hate to see after all these replies and views that it woudl turn to s***.

most everyone in this thread has some very valuable experiences, and are the foremost protege tuners in the world :D lets all get along.
 
Matthew said:
i know this is a stupid ass question, but how can i check the damn guage when im boosting. lol. every guage people have talked about on here seem to mount to the fuel rail.
Get an electronic unit.

IMG_1644_s.jpg
 
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Matthew said:
wow its only 330 dollars!
well..no one said that turboing your car would be cheap! LOL

I still need to purchase a wideband..and those thing are more expensive than any fuel pressure guage!

Chas:mad:
 
mypfizzle said:
bevis.. that is the pimpest thing i have ever seen.. where is ur headunit at?
that set up is PIMP ASS HELL bevis! ^ LOL who needs a radio when you got all those gauges to look after. :D
 
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