[cableguy0]

I can help scratch a few things off your list. Every major cam manufacturer advises AGAINST soaking lifters. Its not necessary and will actually screw up making a proper valve adjustment because you cant properly set pre-load if the lifter is full of oil. Timing being slightly off wont bend a valve. The only way to bend of a valve is to hydro-lock the engine or have a piston hit the valve. You would have noticed if either one of those happened. There are other causes but generally its catastrophic and your post would read much differently. Your cam lift wouldn't cause an issue even with dead stock vortecs and as a matter of fact is fairly small. Were the rings set properly. Keith Black pistons are incredibly finicky about ring gap and will snap the ring lands off if gap isn't exactly right. I wouldn't use a Kb Hypereutectic piston in a lawnmower. Any chance you can get the noise on video and post it here? The oil pump or distributor could be squeaking. You could have a poly lock contacting a rocker. Tons of things. How loud is the noise?