hi speed return

Discussion in 'PSI Superchargers Tech Questions' started by fasttimesracing, Oct 10, 2010.

  1. fasttimesracing

    Joined:
    Mar 21, 2006
    Messages:
    212
    Likes Received:
    0
    first off all my returns go back to the inlet side of the pump. my hi speed has been capped off. this is on a k valve too. so my idle poppet and my pump saver poppet is tied together with a loop i got from rbs.and it takes two number 6 poppets and hooks them together and turns it into one number 6 male an fitting out the bottom.ok here is what i would like to do. they make a t fitting that would screw right onto the number 6 male an fitting and would have a 6 fitting on both side. the one side i could hook my hi speed to and the other would hook back up and go back to the inlet side of the pump. here is what i would like to no. my motor runs 180psi at the dist block on the nozzles. so i am assuming that it would be more than that at the idle poppet. i want to open the hi speed at 120 psi. so hooking it up that way will the fuel even flow out that way or would it just dead head. hope i explained that to where you understand.ok one more thing even if the poppet had more pressure im only returning say 100 main. would that make a difference
     
    #1
  2. Mike Canter

    Mike Canter Top Dragster
    Staff Member

    Joined:
    Mar 10, 2004
    Messages:
    4,630
    Likes Received:
    189
    When does your motor run 180 psi fuel pressure? Do you have a data logger? That is real high pressure. What is your pump saver poppet crack pressure set at? You want your high speed to come on right after launch and I mean right after. withing .1 to .3 seconds. You need to see what the pump pressure is at staging and then set the high speed poppet crack pressure 5-7 psi above the staging fuel pressure. And yes when you change the main jet you will change the fuel pressure and may have to re-adjust the HS poppet. Your isdle poppet is normally in the 8-10 psi area on a Rootes blower setup.
     
    #2
  3. fasttimesracing

    Joined:
    Mar 21, 2006
    Messages:
    212
    Likes Received:
    0
    i do not run any data logger. that is the psi at the disdt block with a gauge with a tattle tale. i run mud drags and only run 200 ft max. the main thing is can i do the fuel retures as i said in above post or does it have to go back to the tank. my idle poppet is 4 and my pump saver is what enderle set it at whan i got it.car runs great but looking for anything else.i had my idle higher and it would milk oil fast and was slower on 200 ft. i only have a msd 20 also
     
    #3
  4. Mike Canter

    Mike Canter Top Dragster
    Staff Member

    Joined:
    Mar 10, 2004
    Messages:
    4,630
    Likes Received:
    189
    If your fuel pressure is 180 psi at the block then it is a lot higher coming into the barrel valve and probably dumping through the pump saver poppet. Also your idle poppet pressure makes no difference to the actual run performance other than what the EGTs are at staging.

    Your lean outs should return to the tank so you get good flow. Too many returns through the same line can limit the return flow.
     
    #4
  5. SoDak

    SoDak Active Member

    Joined:
    Dec 29, 2006
    Messages:
    1,524
    Likes Received:
    3
    Mike, with a K valve my experience shows very little psi drop so am I missing something or do you think the distribution block and pre BV psi will be within about 5 psi of each other?

    Your milky oil is probably just a result of rich BV leakdown.
     
    #5
  6. Mike Canter

    Mike Canter Top Dragster
    Staff Member

    Joined:
    Mar 10, 2004
    Messages:
    4,630
    Likes Received:
    189
    It varies for some unknown reason. 5-10 psi is a good estimate.
     
    #6
  7. SoDak

    SoDak Active Member

    Joined:
    Dec 29, 2006
    Messages:
    1,524
    Likes Received:
    3
    On the return to tank topic, I'll add that many people return in front of the pump vs the tank and do it succesfully (me included and I return alot of GPM). Probably the most fool proof way is to go to tank, but if not done correctly air bubbles can be made by the agitation of returning fuel and thats not good to feed the pump air bubbles:rolleyes:
     
    #7
  8. suddendebt

    suddendebt Blown Altered

    Joined:
    Aug 16, 2009
    Messages:
    133
    Likes Received:
    0
    Sodak is right about the milky oil, I have had the BV screwed up and it will dumb alot of alky in, in a very short time and really make it look it chocalate milk.
     
    #8

Share This Page