Compression Test, PC- An exercise in mental masturbation Options

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Scenerio: You buy an engine and do a compression test. Cylinders measure 135, 130, 130 & 85 - BUMMER. So, since this engine has not run in upteen years, you throw it on the lift and pull the valve cover on the 3/4 side (#4 cyl is the low one).

Lo and behold, you notice that the #4 exhaust valve rocker has no adjuster screw or lock nut and there is a v-shaped piece of aluminum missing from the rocker box beneath the #4 intake valve. Futher probing (Aaron would like that) with a magnet reveals the missing parts.

Great story, but not the point of the post.

Problem:

If the exhaust valve is not opening to relieve the pressure, allowing kinetic energy to pull a larger charge of air into the cylinder when the intake opens, it will not build cylinder pressure like a normal compression test of a cylinder that is working. This is my theory anyway.

I have already been told by one mechanic that I am full of shit and another that agrees with me. No I haven't redone the compression test since replacing the screw and locknut.

This is your chance to mentally masturbate and tell me if I am full of feces or not! Spew away.

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Not sure of anything - like I said, it is an exercise that I can't prove until I do another compression test. The rest of the theory would be that since the cylinder is already pressurized, at overlap the pressure would be released into the intake tract (much like a reversion wave) decreasing the intake charge volume.

Hey, I had nothing better to do than think of this or I could go back to hijacking threads. (IMG:style_emoticons/default/laugh.gif)