Oh shoot i just saw this. Yeah i still have it.

I did a lot of my own diagnostics and thought timing chain stretch as well. I had a misfire on bank 1 as well. What the shop believes is a lifter was sticking. I saw intake valves move turning engine by hand with intake off, but cant see exhaust valves obviously. Pulled cams out and most lifters on entire bank had light scoring. I believe poorly engineered key slot promotes dry start ups. If slot was flippes 180deg it would hold some oil for start up.

Anyway, bought completely new head used and awaiting install this week. Apparently, at idle not enough pressure causes lifter sticking with scoring, but anything above idle allowed free movement and great operation.

Anything else? Just message me.

Adam