hey Firebird: ours doesn't have a pcv valve, has the road tube and breather cap on the oil fill tube. (both are clean and working) from the start I can't believe either the grease being a problem. R Pope: Bet that baby burned oil! (I'll admit I"ve had a few "dumb" things in the past I've done). 81 Cabellero: It would seem rings are seating by compression test. We're going to redo the leak down test to be sure. We did change oil right away after second rebuild, and for good measure put a few miles on and changed it again. Corvette64: Love that generation of vette's. It usually takes about 5-8 minutes to start smoking. One would hope this would eliminate the seals, but won't hurt to look at them again. (we're using o-rings and umbrella seals). We are considering pulling the intake and see if it is cracked somehow. I've been told on sand castings about sand shifting and could have a thin layer somewhere that cracked. One would think a crack would have to be in the right place (like the plenum) to get oil on both sides of the dual plane. If it was cracked only on one runner, one would thing it would affect 1-4 cylinders, but not all eight. There is a chance though it could "distribute" under the carb to crisscross to the other cylinders.