Could be lack of oil return holes to the bottom. Those blocks don't have much for oil drain back holes. Could be pumping the oil pan dry, with not enough time to drain back. I have seen this before with those blocks. Otherwise, there should be no issue. Those are a dry sump or wet sump block, so, if you run it wet, you need to add some extra drain back holes in the lifter valley. They do that, so, when you dry sump it, you can keep the oil where you want it.
Frank
Advanced Performance
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