need spec information 1971 olds 455

Discussion in 'Gas Engines' started by big570bear, Feb 19, 2011.

  1. big570bear
    Joined: Feb 2011
    Posts: 4
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    Location: bullhead az 86442

    big570bear New Member

    doing a compression test on my 71 olds 455 , been trying to get a handle on what the minimum psi should be per cylinder?????????? if anybody happens to have that on hand please give me a shout. thank bear
     
    big570bear, Feb 19, 2011
    #1
  2. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    It depends on the compression ratio the engine was built to. Assuming it is no more than 9.5:1, the minimum is about 125psi. It may start under that but will show a pretty worn engine. Also, do a dry and wet compression test. That will show if there is wear in the rings and pistons.
     
    gonzo, Feb 20, 2011
    #2
  3. big570bear
    Joined: Feb 2011
    Posts: 4
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    Location: bullhead az 86442

    big570bear New Member

    gonzo I'm sure it is 9;5;1 according to the information i have already received. thank you for your reply bear
     
    big570bear, Feb 20, 2011
    #3
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