Fuel Pressure Regulator

Discussion in 'Fox 5.0 Talk' started by Makdaddymac, Oct 30, 2009.

  1. Makdaddymac New Member

    Member Since:
    May 29, 2005
    Message Count:
    336
    Likes Received:
    0
    Trophy Points:
    0
    changed my fuel filter,and i think i had the fac filter:mad:,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).
  2. 5.0Droptop Neutered Member

    Member Since:
    May 16, 2002
    Message Count:
    6,938
    Likes Received:
    772
    Trophy Points:
    173
    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.
  3. Makdaddymac New Member

    Member Since:
    May 29, 2005
    Message Count:
    336
    Likes Received:
    0
    Trophy Points:
    0
    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
  4. 5.0Droptop Neutered Member

    Member Since:
    May 16, 2002
    Message Count:
    6,938
    Likes Received:
    772
    Trophy Points:
    173
    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.
  5. Makdaddymac New Member

    Member Since:
    May 29, 2005
    Message Count:
    336
    Likes Received:
    0
    Trophy Points:
    0
    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?
  6. 5.0Droptop Neutered Member

    Member Since:
    May 16, 2002
    Message Count:
    6,938
    Likes Received:
    772
    Trophy Points:
    173
    If its running fine I would say everything is most likely ok.
  7. cenok is family New Member

    Member Since:
    Jun 26, 2003
    Message Count:
    1,268
    Likes Received:
    0
    Trophy Points:
    0
    mine runs to the vac tree on the underside of the plenum. I'm pretty sure that's the factory location
  8. Makdaddymac New Member

    Member Since:
    May 29, 2005
    Message Count:
    336
    Likes Received:
    0
    Trophy Points:
    0
    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?
  9. GTOreturns Active Member

    Member Since:
    Oct 1, 2003
    Message Count:
    1,330
    Likes Received:
    3
    Trophy Points:
    38
    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.
  10. Makdaddymac New Member

    Member Since:
    May 29, 2005
    Message Count:
    336
    Likes Received:
    0
    Trophy Points:
    0
    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.:shrug: 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...:shrug: 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.....
  11. cenok is family New Member

    Member Since:
    Jun 26, 2003
    Message Count:
    1,268
    Likes Received:
    0
    Trophy Points:
    0
    my car is originally SD. i converted it a few years ago.
  12. Mustang5L5 Founding Member

    Member Since:
    Feb 19, 2001
    Message Count:
    19,550
    Likes Received:
    4
    Trophy Points:
    78
    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.
  13. Makdaddymac New Member

    Member Since:
    May 29, 2005
    Message Count:
    336
    Likes Received:
    0
    Trophy Points:
    0
    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....

Share This Page