sorry for the long story
engine background: good 4g63 engine, no balance shafts, arp studs, oem fiber gasket, tear drop oil port mod done to head, haven't had lifter tick with 1g lifters since start up (almost a year on it) no leaks, no oil burning, been a solid runner, short block was used and came from myles, i checked it over and as suspected since myles is such a stand up guy, everything was legit, head was used and was taken to a machine shop, cleaned, inspected, new seals, no issues found.
So a month ago I went out for a cruise with the 4g63 swapped wagon, nothing hardcore just driving around, take off from a stop light, shift into 2nd gear, hear this weird sound that's the speed of lifter tick but louder, think 'wtf just broke' and i pull into a parking lot, open the hood and listen, sounds weird, not like lifter tick, but i think 'maybe it is, i have been running revised lifters for so long, maybe i dont remember what it sounds like!' I give it a little rev and think 'man that sounds weird.'
So i shut it off and let it cool a little while, kick back and relax, check the oil level, start it back up after 15 minutes, sound seems to be gone. i decide to drive home and investigate further. Get home, pop the hood, check timing belt tension, check oil again and look for any shimmer, none found. start it back up and let it idle, sit there in a lawn chair for 10 minutes watching it idle and listening to it, bring revs up to 3k, hold them, let off, bring back up, feather it around, finally get it to do the sound again, keep fucking with the throttle; up, down, hold, up, down, a, b, a, b, select, start. Sound goes away (didnt actually do the a,b,a,b part, duh)
Decide it's valve train noise, go inside, buy revised lifters, figure since im in there i might as well replace the old stock units.
lifters arrive lighting fast since Eric Jones is the shit, pull apart my valve train and inspect, see no issues, no collapsed lifters, check anything i can check, install all the new stuff, start it up and wait for the new lifters to pump up. once pumped they sound great, sound like the old lifters did before the weird noise, i fuck with the revs again, get the sound to happen again, get pissed, shut it off, go inside, kill myself. well, except that last part.
come out the next day, start it up, sounds even better, mess with the rpms, sound doesnt happen, i start to question my brain and think that lifter noise has been the issue the whole time. drive the car to work, no issues. at work start searching for valve train noises not related to lifters, find stuff on this board about cracked rocker rollers, think 'oh my'. go home and remove VC again, slowly crank over engine by hand and inspect all the rocker rollers, find no red flags, put back together, go out for a drive, no noise...
drive it 3 hours to a car show in detroit, all is well, no noises. drive it 2.5 hours home, noise comes back half hour from home, i pull off, grab a tea, let it cool off, browse the web for a bit, thank some rednecks for stopping to see if im ok, have a short conversation with an old guy who's wife used to own a 75 wagon, start the car back up, sound is gone. drive softly the other 30 minutes home, park the car and dont drive it for 3 days.
Come back out, drive it for a week, swap in a KM132 transmission, drive it a bunch, every day in fact, until monday of this week, noise comes back.
searched the web throughout the week and finally found a video that sounds similar to it.
dont mind the commentary, just listen to the engine noise, my car doesnt have balance shafts (incase you're a youtube comment reader)
Thanks for reading and here's a recent picture of the booger bay: