The one in post 19 worked for me but u didn't rev it.
the first link works now, wheres the 2500 rpms and drop to idle?
it does sound more a rocker or busted spring now
I'd be pulling the valve covers. Does sound like something's broke in there. Definitely isn't lifter "tick". Broken spring or bent pushrod maybe.
Yeah, sounds lifter/rocker.
It's half the speed of the crank for sure, good tick to it.