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horsepower question

Discussion in 'Early CJ5 and CJ6 Tech' started by EmilyMcDangerous89, Mar 27, 2010.

  1. Mar 27, 2010
    EmilyMcDangerous89

    EmilyMcDangerous89 New Member

    Lakeland, Florida
    Joined:
    Nov 18, 2009
    Messages:
    13
    Ive got the f-head engine in my jeep, its bored .80 over. Each .10 the f-head gets bored over, how much horsepower does it to the crank and the rear tire? Thanks in advance!
    -Em.
     
  2. Mar 27, 2010
    Patrick

    Patrick Super Moderator Staff Member

    Los Alamos, NM
    Joined:
    Sep 22, 2002
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    8,360
    .80? :shock:

    ;)
    That'd be .080..
     
  3. Mar 27, 2010
    Eaallred

    Eaallred Member

    West Valley City, UT
    Joined:
    Oct 9, 2008
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    188
    It would be pretty minimal, nothing you'd feel by "seat of the pants". Consider head, valves, intake, exhaust, cam, etc, etc, is all the same.

    The small amount of displacement increase doesn't amount to much, even on a dyno to see the results.
     
  4. Mar 27, 2010
    duffer

    duffer Rodent Power

    Bozeman, MT
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    Sep 17, 2009
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    4,514
    I poked a couple out .080 and there was a very notable increase in power- 99.99999% of which I attributed to actual functioning rings:D

    Greatest bang for buck will still be a high compression head. You might get a hp or two out of .020 or .040 overbore, but it will not likely be something you will actually notice.
     
  5. Mar 27, 2010
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Aug 10, 2003
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    23,596
    Calculate what the displacement increase is and the power increase will be close to that amount. Might be a little more than that, because the compression goes up slightly too.

    <edit> The bore of the 134 is so small, that 80 over (remarkably) increases the displacement by about 5%. If I knew the combustion chanber volume, I could figure the increase in compression too.

    I expect the larger bore and the increased compression ratio will make a noticeable difference in this case.
     
    Last edited: Mar 27, 2010
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