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Compression psi?

Discussion in 'The Garage' started by mpascino, Dec 28, 2002.

  1. mpascino

    mpascino 1/2 ton status

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    Hey guys, sorry it's been a while, been real busy. Anyways, what compression readings should be expected from an 8.5 compression ratio engine. Correct me if I am wrong, but Standard ATM is 14.7 psi. With a compression pressure 8.5 times as great -> ~~125 psi? Am I missing something here? I have someone telling me my compression pressure in my olds 350 should be 160 psi. What do ya think. I don't have any of my service manuals down here with me.
    Thanks in advance,
    Mike
     
  2. mpascino

    mpascino 1/2 ton status

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    Location:
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    I just realized that my compression ratio is actually more like 7.75 after all the engine work and thicker gaskets..... /forums/images/graemlins/frown.gif It's a daily driver for now so no biggie. Anyways, after modeling the motor in my engine program compression psi should be around 133, accounting for normal loss. So my measured 125 isn't bad at all. This still leaves me baffled. How the heck would one go about calculating the actual readings that I should have. I think my thermo fluids class history is getting kind of rusty........
    Thanks,
    Mike
     

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