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  1. #1
    "just sayin".. jetdave56's Avatar
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    normal stock compression

    on a slightly warm engine run 5 mins and then each cyl. tested, i ran , 115, 115, 115. happy that all #s were exactly the same , but some what low???, the compression tester i have has adapters, the male one going in the spark plug treads fine but the othe female end going into the male end of compression hose does'nt really thread , slightly wrong size, maybe leaking air slightly, are these #s low for stock?


  2. #2
    Mike xsockguyx's Avatar
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    What type of guage is it?

  3. #3
    "just sayin".. jetdave56's Avatar
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    gauge

    mike , a real cheap one, like a ebay store , if i remember, i think i need the correct adapter, why?, do those #s sound low?, should'nt i be running 125-130 psi?

  4. #4
    Happily Self-Employed WFO's Avatar
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    EFI PV motors are usually 115-120ish

    EFI non-pv are usually 130-135ish

    all EFIs are a few psi lower on #3

    could just be the gauge

    when checking compression:
    -make sure the PVs are closed/down (when applicable)
    -leave the other 2 spark plugs in
    -open the throttle
    -make sure you have a good charge on the battery

  5. #5
    "just sayin".. jetdave56's Avatar
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    psi

    rich,all that is done,im going to sears to get a new one, but i'm going to have to test it on the new milled heads, i expect to "bend that dial" all the way back!

  6. #6
    Happily Self-Employed WFO's Avatar
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    just so they are all pretty consistant, you are golden!

  7. #7
    32 Valves To Love! Racecar_Dave's Avatar
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    115 for a PV EFI motor!? I have really high stock compression, maybe I'll leave it that way, who has the fastest stock compression gpr?

  8. #8
    Quote Originally Posted by jetdave56 View Post
    on a slightly warm engine run 5 mins and then each cyl. tested, i ran , 115, 115, 115. happy that all #s were exactly the same , but some what low???, the compression tester i have has adapters, the male one going in the spark plug treads fine but the othe female end going into the male end of compression hose does'nt really thread , slightly wrong size, maybe leaking air slightly, are these #s low for stock?
    Dave , this is not the procedure for checking compression...
    you should be in the 130`s stock, and depending on how tight your modded head is you should see 145+

  9. #9
    fenn's Avatar
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    Quote Originally Posted by Pale Rider View Post
    Dave , this is not the procedure for checking compression...
    you should be in the 130`s stock, and depending on how tight your modded head is you should see 145+

    115?

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