Sd66,
The symptoms you are describing, in my opinion, exactly point to the valve guides as the smoking problems on deceleration, idling, and any other high vacuum conditions.Not only SBC but, other engines with copious oil supply overhead, will smoke and foul plugs and "use oil" from valve guide leakage even with perfect cylinder and ring conditions. But, that being said, I can't reason that as a source for excess venting from the crankcase. I have never had a problem with long break in of chrome or moly-chrome rings when the cylinder size, finish, and shape was NEAR correct--even with re-ring of cylinders that should have been resized. The OEM has used chrome or Chrome+ rings as an industry standard exclusively since the mid 50's.The ring makers/designers stated years ago cylinder wear(cast iron) is reduced at least by 75% when chrome top and oil ring is used.I will(and have) pay extra to get top quality plated or filled rings. Our choice of guide seals were the Perfect Circle VS2 for the small block but as of recent times they are hard to find here and the Fel-Pro and equivilent for modern engines made of viton are easier to find--the catch with both is that the top of the guide is not machined to fit like the factory did about after 1965 (Hell, we aint got no problem)--finally they saw the light.The machining is done with a tool in a hand held 3/8 or 1/2 drill with the valve REMOVED.Takes about 10 seconds per guide and most head shops have what it takes.If you have trouble finding the tool, contact me and I'll loan you one.
