Hey everyone! Thought I'd give somewhat of an update. I pulled the engine again. Boy, I'm getting good at that! Anyway, when I pulled heads, I noticed an excessive amount of oil/fuel "gummy" stuff on the piston tops and the combustion chambers. Nothing foreign had got in there like we thought tho. No physical damage at all. Guess that's good. Got everything off engine except the rotating assy. When I spin the engine with a ratchet, I hear the "thunk" sound that is what I think I heard when it was running. More than one "thunk", multiple...If I put my hand on any piston and rotate the engine, I can feel the "thunk". I can rock the piston as it goes up and down. Pulled one (for now) measure it and it is 4.355" This is a 440 + .040, so .005 piston to wall. Too much?? Is the piston supposed to rock like that?? Remember, I'm using the 440Source 512 kit. Icon pistons. Also, seems like a lot of ring grind in oil. Oil is very "grey" in color and gritty. Bearing look like new. The rest is gonna come apart tomorrow. I just wish I could see something definitive! Still can't explain why no power either. Mystery! Thanks everyone! Jeff