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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Fuel Pressure Regulator

  • Thread starter Thread starter Makdaddymac
  • Start date Start date Oct 30, 2009
M

Makdaddymac

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May 28, 2005
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Oct 30, 2009
#1
  • Oct 30, 2009
  • #1
changed my fuel filter,and i think i had the fac filter,feels like i picked up some horses which got me thinking....
i have been doing some research about tuning my car a little)(SD.)....so that leaves me with fuel pressure and timing correct?

the only thing i haven't checked is fuel psi.... i have a few questions though....
the regulator has a vacuum going to it, that goes to the egr vacuum port? is this really enough vacuum or should i connect it to a better source. intake or something???

should i get an adjustable fpr. (def going with the kerwin unit if i do).
 

5.0Droptop

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Special Agent Mukity-Muck Whats in Charge Round Here
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Oct 30, 2009
#2
  • Oct 30, 2009
  • #2
Yeah fuel and timing is what I always played with on my SD set up. It never hurts to have a adjustable regulator. I always ran my vac line right off the intake.
 
M

Makdaddymac

New Member
May 28, 2005
323
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Oct 30, 2009
#3
  • Oct 30, 2009
  • #3
would lil to no vacuum to the regulator negatively effect me? im sure it would, but i know its not getting much especially if its feeding off the egr vaccum which really cant be the best source....
or is this factory to run from egr to fpr, i cant remember if i put this on wrong or not when dong my top end work
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
1,785
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Indiana
Oct 30, 2009
#4
  • Oct 30, 2009
  • #4
No vaccume will let the fuel press go high as the regulator will let it go. When you apply vaccume the press will lower about 5psi or so.
 
M

Makdaddymac

New Member
May 28, 2005
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Oct 30, 2009
#5
  • Oct 30, 2009
  • #5
okay so, my current setup is sufficient enough then? cause i was worried it wasn't getting enough/more vacuum, and i dint know if this makes for lower psi.....basically would more vacuum be better?
and what is the max i can run with an adjustable. will notice any gains from this?
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
1,785
1,130
233
Indiana
Oct 30, 2009
#6
  • Oct 30, 2009
  • #6
If its running fine I would say everything is most likely ok.
 

cenok is family

15 Year Member
Jun 25, 2003
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Norman, Ok
Oct 30, 2009
#7
  • Oct 30, 2009
  • #7
mine runs to the vac tree on the underside of the plenum. I'm pretty sure that's the factory location
 
M

Makdaddymac

New Member
May 28, 2005
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orlando
Oct 30, 2009
#8
  • Oct 30, 2009
  • #8
well maybe the SD and MAF cars have diff ways???

so if i unplug it and notice a difference for the better, is it cause im getting more psi?
 
G

GTOreturns

Well-Known Member
Oct 1, 2003
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Oct 30, 2009
#9
  • Oct 30, 2009
  • #9
Makdaddymac said:
well maybe the SD and MAF cars have diff ways???

so if i unplug it and notice a difference for the better, is it cause im getting more psi?
Click to expand...

It's suppose to be plugged in so leave it in. The only time it comes off is when u change the pressure. Whick you can't because the factory reg has no adjustment.
 
M

Makdaddymac

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May 28, 2005
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orlando
Oct 31, 2009
#10
  • Oct 31, 2009
  • #10
i know that, im just really trying ot figure out if more vacuum is better for the regulator, i also just want to see if runnig with no vacuum( should give me more psi right) which could then see if it runs better, which would then give me more reason to buy an adjustable....thats my logic. not sure if its logical but thats that. i guess there is only one way to figure this out.....

also, would a faulty tps or out of voltage range hurt wot perfromance or is it just for idle? as well as the idle air control valve... i have a slight hunting ilde and its either the tps or air valve......would either of these hurt wot performance???

idk no why but everyday i see myself dumping money into this car and i see what a waste it is, i am so tempted to sell it everyday.....
 

cenok is family

15 Year Member
Jun 25, 2003
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Norman, Ok
Oct 31, 2009
#11
  • Oct 31, 2009
  • #11
my car is originally SD. i converted it a few years ago.
 

Mustang5L5

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Mod Dude
Feb 18, 2001
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Oct 31, 2009
#12
  • Oct 31, 2009
  • #12
Makdaddymac said:
well maybe the SD and MAF cars have diff ways???
Click to expand...

Nope, it's the same. The vacuum for the FPR runs directly to the little "tree" under the intake plenum.

I'm still SD...and that's how my car was from the factory.
 
M

Makdaddymac

New Member
May 28, 2005
323
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0
orlando
Nov 2, 2009
#13
  • Nov 2, 2009
  • #13
ok well my car def has the egr connecting to the fpr.....and the tube that does it is aperfect length, i must have messed something up with my gt40 install, because i guess the egr and fpr are suppose to have vacuums going to the intake? i can just run it to the tree on the firewall correct? there is a unused vacuum source, or should i just t-off another source....
 
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