[Formulas]

Originally Posted by dataway

It would be weird if it ended up being something like the valley pan flexing under fluctuating vacuum signal ... like popping the bottom of a tin can back and forth.

The PCV valve by virtu of being in the pushrod cover helps to make the sound bigger like a drum skin

This isn't a theory or guess circa 1982 I put a p4b intake on my 1968 GTO removed the q'jet intake I totally forget what carb I used but i plumbed PCV through a front runner and thought i hurt my engine by foreign debris because it was making noise and idle was not as smooth

Since I am not in front of original poster's engine I won't go as far as to say this is his problem but its soooooo EASY and cost nothing to check to eliminate.

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