compression test

Discussion in 'Technical' started by 71comet, Mar 4, 2006.

  1. 71comet

    71comet Member

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    Hey everyone,

    Does anybody know what the compression numbers are for a 71 250 6cyl? I want to test the cylinders to see what I am working with but I have not purchased a manual yet. I would appreciate any help you could give. Thanks again.

    Scott

    71 Comet GT:bananaman
     
    71comet, Mar 4, 2006
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  2. 74merc

    74merc computer nerd

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    Consistancy is what you're looking for. If memory serves, they should all be within 20%.

    For a ballpark number, depends on compression ratio (should be around 9:1 on that one) and camshaft (smaller camshaft, higher compression numbers by the guage to a degree), it should be around 120-140psi. My 8:1 compression 302 with a 260ish cam is 138psi, my dad's 8.5:1 350 with a 250ish cam is 178psi.
     
    74merc, Mar 5, 2006
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  3. 71comet

    71comet Member

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    Thanks for the reply, at least I have a starting point now.


    Scott:bouncy:
     
    71comet, Mar 5, 2006
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