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  1. #1
    dpracing's Avatar
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    Would an 8 pound difference in one cylinder create a slightly rough idle?

    Just curious on your thoughts.


  2. #2
    imp0ster's Avatar
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    8lb difference is nothing as long as your lowest number is still within spec.

  3. #3
    dpracing's Avatar
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    Quote Originally Posted by imp0ster View Post
    8lb difference is nothing as long as your lowest number is still within spec.
    Thanks. The lowest number was 137. Others were both 145.

    Idle is a little rough. It's a stock tune. Afr at idle is 13.6.

    Maybe a dirty injector?

  4. #4
    Got Boost? psycho rxp's Avatar
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    13.6 is a lil lean, bump fuel pressure up to get 13.2 @ idle to see if that helps, if u have a pressure reg.

    or leaky intercooler

  5. #5
    wotxxxsd's Avatar
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    I've seen a difference in compression #s when carbon was built up on the valves.
    Maybe you have some build up?

    Rough idle could be some sub par fuel or partially clogging Injectors..

    Sweet looking machine you've got!!!!

  6. #6
    dpracing's Avatar
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    Thanks for the replies.

    I want to do a leak down test. What is the procedure you guys use as far as getting each cylinder on tdc?

    I have the manual and its is very vague. It seems like you use the starter to bump the motor around and then use a tool on the drive shaft w the pump out to dial each cylinder in?

    What do you guys do ? I need a pros advice. Thanks !

  7. #7
    speedskixp's Avatar
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    I prefer to just put #3 top dead center and pull the rocker shaft to be sure all valves are closed.

  8. #8
    dpracing's Avatar
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    Quote Originally Posted by speedskixp View Post
    I prefer to just put #3 top dead center and pull the rocker shaft to be sure all valves are closed.
    How do you rotate the engine? Starter?

    Can you re- use the rocker shaft bolts? I thought I read they need to be replaced when you do a valve train kit? Stretch to yield?

    Thanks

  9. #9
    dpracing's Avatar
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    TTT

  10. #10
    Are you trying to do a leak down percentage test? or air each cyl up to see if the air Leakage is coming from the Intake, exhaust or crankcase? 2 different test. Requiring 2 different tools.

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