Newbie question

Discussion in 'PSI Superchargers Tech Questions' started by Money Shot, Apr 13, 2009.

  1. eli

    eli Banned

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    Check your pm's
     
    #21
  2. BLOWN INCOME

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    My experience would say WAY to lean at the hit ! Ours with lenco drive in a altered would'nt move 1 inch without blowing tires of or being on limiter...increased b.v.to 86 % and added two more nozzles, now .960 60'.......
     
    #22
  3. paint guy

    paint guy Member

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    is there enough fire in the msd 10?i had the same problems once until i changed to a mag.
     
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  4. Money Shot

    Money Shot Member

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    good point Ill check my voltage
     
    #24
  5. paint guy

    paint guy Member

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    no i mean does the msd 10 put out enough fire to make your combo run?my problem was my msd ignition that i had at the time was'nt enough fire to make my motor run.if the car hooked and was under a load it would pop and miss all the way down the track if it was spinning or just reving it up in the pits it sounded fine.i went through everything and at last changed to a mag and it cleared up.it may not be your problem but thats what i went through.
     
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  6. crashly

    crashly Member

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    can you put an alternater on it?
     
    #26
  7. Flyboy68

    Flyboy68 Member

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    You guys might clarify what you mean by "72%" & "86%" leak. To me 86% that would be leaner at the hit. Some see that as 86% of the fuel is leaking back to the tank which would mean 72% would be fatter.
     
    #27
  8. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    fuel system

    it should be added you might find better results quicker by having a notable fuel system guru flow your system and give you a better baseline. I'm sure Gorr has quite a bit of experience with these Chevy motors.
     
    #28
  9. eli

    eli Banned

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    It's how much fuel will go true the barrel valve, 80% is More fuel than 72%. capeash? At 86%, At full throttle the barrel valve goes over center and you will be lean. :eek: ;)
     
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  10. Mike Canter

    Mike Canter Top Dragster
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    Eli, I guess I don't understand what you are saying there. In the K Type barrel valves I have seen running them at 86% leakdown still does not make the barrel inside go over center and restrict the flow at WOT. Maybe it would if one had a leakdown tester that was way out of calibration so 86% was really way more. Has anyone else experienced that?
     
    #30
  11. eli

    eli Banned

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    Mike if you look at the spool where the arm from the turnbuckle mounts to, There is a notch, if that notch is past parallel to the In fuel line and the out to the hat line then it is over center, all spools have this notch, Hilborn, Enderle, Kinsler, some where between 86% and 90% depending on the gage is when this happens. and at W.O.T. the motor goes lean.
     
    #31
  12. Flyboy68

    Flyboy68 Member

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    Clarify...if your first gage is set to 100 psi, at 86% leak would your second gage read 86psi or 14psi???

    Also it's borderline impossible to get off center by being off on the leak down...if the barrel valve valve was that big there would only be one leak down percentage you could be at before restricting flow at wot.
     
    #32
  13. mbaker3

    mbaker3 New Member

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    On my tester, the second gauge tells me what percentage is leaking by to the hat.
     
    #33
  14. Flyboy68

    Flyboy68 Member

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    Which would mean "0" or the dial being all the way to the left (counter clockwise) would read 100%. No back pressure means no restriction...100% flow. If your gauge reads 0-100% that would be telling you how much is bypassing to the tank. ie- your gauge reads 82%...that's 18% going through the barrel valve to the motor...and 82% going back to the tank.
     
    #34
  15. Mike Canter

    Mike Canter Top Dragster
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    On a standard leakdown tester set at 100 psi then 86% would read 14 psi. If the idle return poppet is capped off and the Barrel Valve outlet hose is disconnected and is open.
     
    #35
  16. mbaker3

    mbaker3 New Member

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    I cap off all return lines before running the test leaving only the line going to the rear distribution block open. The leak by should show what is actually going to the hat nozzles.:)
     
    #36
  17. Bob Meyer

    Bob Meyer Comp Eliminator

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    B.V. Leak

    Mike, Eli, and anyone else who may care:
    We all know a system should be flowed and a GPM number established for idle. As this thread rolls on, we see not many understand this, let alone do it.
    NEVER throw out a leak number of your own, or SHOULD be number. Those K valves and spools may sure look alike, but ARE THEY ??

    One example: a certain batch of K valve bodies only had one step in the bottom. Most had two, the smaller being a
    .187 to match the spool hole. The other, I think was a .220 hole where it met the spool. If you set your leak at 72%, pulled the bottom plug, got a mirror face up under the valve with the big hole, you would see a 1/8 moon of the spool hole. So, experience says 500-550 *, but you've really got 800-850*, you happen to own a casting that has to have 84% to achive the desired 500-550*!

    It doesn't mean it's junk, just different......
    I don't know many people that have actually measured the hole in their own spool either, so we'll let it be said there is only ONE right way, the flow bench!

    And don't get me started on leakdown testers, I don't type that well. But I will say this: get a jetholder and plumb it to your tester. Screw in a .060, give it air, it should read 60%, try a .080 jet, you'll get 80%, if you don't get these numbers, get your tester calibrated. This ain't my deal, it came straight from US Weights and Measures according to the Sunnen man.

    Std. disclaimer: I'm just a welder.
     
    #37
  18. Ken Sitko

    Ken Sitko Super Comp

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    Bob, if in doubt about the leak down, I look through the inlet fitting of the barrel valve, and set the spool so most or all of the V opening is exposed. Fire the car, bring it up to 5500 rpm, and you should get a bit of alky spraying out of #1 and 2 pipes. Has always worked for me.
     
    #38
  19. Alkydrag

    Alkydrag Sr. Dragster

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    If I remember correctly, Drazy said the .187" was for funny cars and the
    .220" was for dragsters. Or vise versa.
     
    #39
  20. kosky racing

    kosky racing Comp Eliminator

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    leakage testers

    I am making leakage testers that do the same as the old sunnen testers .I will have them with me at the races if anyone is interested in them.
     
    #40

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