Hi, I've been running my 1930 Model A for 21 years with an oil pressure issue. The engine is great and as I said no issues for all these years. The engine is a stock bore 1970 Dodge/Chrysler 383. I acquired this engine as a "recently overhauled" unit. During the car build, I pulled the heads to see the bores. Honing was still clearly evident and no lip so buttoned it up and carried on. First thing I noticed was when the engine was fully warmed and in gear, the oil pressure was only 10psi. Touch the gas and it goes to 30+. While the car was blown apart for paint, I delved deeper into the engine. Crank was badly scored, so ditched everything but the block. Machine shop fully prepped the block and I reassembled it with a perfect replacement rotating assembly and rebuilt heads. Car gets final assembled and on initial firing, the same condition occurred. I and my favourite shop chased this issue several times. There's lots of oil getting to the top when its running with low pressure. Cold start 50psi+ warming to 180° after driving a bit then stop at a light in gear and its 10psi. Touch the gas and its 35psi. all day long. There are no oil leaks into coolant or externally. My most excellent mechanic figures the block is porous somewhere and I agree. There is no engine noise like cam bearings or something and the condition carried over into the new assembly with all different parts. Does anyone have any experience on how to trace or prove a porous block?