Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Welcome, I'm Chris (aka Moose).
This noise is most likely related to the valve train. I see alot of lifters that fail and cause this type noise you are describing. This noise would come eithin the center of the engine near the valley under the intake.
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I have seen spun bearings but that should result in low oil pressure and usually a constant squeak and no tap noise. A rod bearing could cause a squeak and tap but again oil pressure would be affected and it is just not as common as the lifters.
If yours sounds identical then that does appear to be a lower end noise. It is time to remove the pan so you can start the inspection process on the main bearings, thrust washer, and rod bearings.