We finally got around to disassembling the original 350 engine from the S71 Olds project. We found a pretty significant amount of sludge, but no major damage at this point. This engine had never been apart before, although it appeared one valve cover gasket had been replaced, as one side was clean and the other was pretty grungy. It's another example of why you want to run synthetic oil! However, seeing that this mill dates back to 1971, some gunk was to be expected.