Your oil is way too thick for the application... Your filter choice is perfect.... Try using a 5W-50 synthetic... From what you've written, the tap should vanish. The thick oil does not flow into precise components like lifters until it warms up.... Check your timing marks on your balancer, as they maybe off. Bring #1 cylinder up to TDC, and record timning mark.... Clevelands like in the low teens advance numbers, IIRC....

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