Peter J. Thomas wrote:
> Ok, here is where I show my stupidity.
>
> Bought my first compression guage. It is calibrated in psi. How do I
> determine the compression ratio? Ie. how do I convert x psi to n:1?
>
> Peter Thomas
Thanks for all the replies. I suspected much of the theory but didn't
have anyway to confirm it. Even if the was a little magically formula, I
doubt the cheap little gauge is that accurately calibrated.
Just as a follow up, the car I was testing is a 91 Ford Tempo with a
compression of 9:1. The readings I got were 135, 140 130, 125. There is
a 15 psi (11%) difference between cylinders 2 and 4. Probably not worth
worrying about. This did confirm my suspicions about cylinder 4, but it's
not that bad.
Thanks again,
Peter Thomas
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