Got the video to work. Sound is in the valve train - not bottom end. Bolt-down (non adjustable) rockers can only "gain" clearance by the following:
Lost a cam lobe
Collapsed lifter
Bent pushrod
Damaged roller rocker (which you don't have).

Other sources for valve train noise are
Sticking/bent valve
Broken spring or damper
Loose valve seat

Isolate the problem cylinder by removing one rocker at a time. You'll need to keep finger pressure on the push rod to keep the lifter from popping out if its bore - unless you run stock GM Dog bone roller lifters which are trapped by the orientation plate. I can't recall if your motor is a roller or not.

If you run dog bones you can remove as many as you want.

I'd try another oil filter first,,doesn't seem like alot of oil up on the top end.

Wish I had better news. Dropped valve seat on the number 7 exhaust valve.

http://i1361.photobucket.com/albums/...ps7hvjg72d.jpg


http://i1361.photobucket.com/albums/...psdnsqfhex.jpg

http://i1361.photobucket.com/albums/...psuag46r5c.jpg

That blows! At least you caught it early. Still plenty of season to go!

That blows but you got off relatively lightly. My engine was destroyed when my valve seat departed.

What does other side look like? If no worse than this, you need a pair of heads. 990's are easy to find. I only have 1 spare set, but I know of a guy with some. Hell, half the people on OSO know where to find a set of these...oh, that is both sides...edit again. I was thinking of diff thread with guy with low comp in 7 and 8.

At least it looks like the piston got ugly, but not killed.

I would be jumping right on a rebuild if I hadn't already spent 21,000 this off season. she's gonna sit for a while before I spend money on a rebuild most likely.

That's a bummer, spend that kind of coin and not have it last any longer then this.

put heads on and do a compression test.