oil pressure

I think the problem is that you shimmed the spring. That is why you have such high cold pressure. Take the shim out and/or put in a soft spring and then shim the soft spring to get you the correct pressure at speed. Typically with a high volume pump you need to run a shimmed soft spring to get the correct balance between oil pressure at idle and at full throttle.
Andy, Where do you typically read oil pressure when working on your big blocks?

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