The rocker and cam problems may be related. I assume you have an adjustable valvetrain for a healthy cam, and drive it fairly hard to 'break loose a rocker.' A cam can be precisely checked for lobe condition by setting up a cheap dial indicator on each valve and checking max lift. Any lobes worn more than about 0.005" should be considered junk, along with the lifters.There's tremendous leverage on the rocker pivots especially if you float a valve. I suggest using Ford/SVO rocker studs and a stud girdle when you assemble the heads for your next round. I also suggest roller rockers and all-new pushrods, plus the complete engineered kit for the new cam. Boss one-piece, single-groove valves are safer than stock welded two-piece valves and their multi-groove keepers. Stock valves can break in half at high rpms and stock keepers often release valves at high rpms. A rev-limiter might be a good idea, too. All this stuff will fit inside the commonly available cast-aluminum valve covers if you remove the sheet-metal baffles.
