Re: 327 oil pressure drop
Start with changing the oil and filter, work up from there. Some assembly lubes have molybdenum which will plug a filter. If that isn't the cure make sure the gauge and sending unit are good. Eliminate all the simple external variables before you drop the pan and change the pump. In the long run you may be looking at improper bearing clearance but that would be the last resort. Always work from easiest to most difficult unless the problem is obvious.
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