I have a few lifters making noise until well warmed up

My truck had a small flange leak and it sounded like chit at idle but it went away at speed, warm it wasnt much better. new gasket cleared it right up. Buddies old 2bbl 302 would rattle those lifters for a full 5 minutes before they quieted down. Drove like that forever. lifters have a small ball check valve in there. There is not much to go wrong in there except maybe a hung up lifter piston. you CAN take them apart and clean them. might even snake them out through the head so you dont have to disturb the intake.