360 runs strange, lifters??

I've been trying to figure out a weird issue with the 360 in my D200 pickup for years. Basically what happens is on rapid decel or when free-revving it, when the revs fall it sounds and feels like it's not running on a few cylinders for a few seconds. Does it worse when it's cold. I went through the ignition and upgraded some things, no change. I thought it might be a phantom vacuum leak, I just installed an Edelbrock 2732 adapter plate to make sure the carb was fully sealing to the Performer intake but it still does it. I recently replaced the timing chain which was badly worn, definitely runs better but still has the same issue. I did notice that if I shut it off while it's running funky then go to restart it kinda sounds like a few cylinders don't have compression. All I can think of now is maybe some of the lifters are pumping down on decel? Idk how the heck that would work but I'm stumped. It does still have the original cam and lifters afaik, according to the odometer the truck has 133k miles on it (had 122k when I got it). Runs like a champ otherwise but this annoys the heck out of me and keeps me up at night lol.