do as fatweed said.check the action of the rocker arms.have to remove the valve cover to check.Check rocker arms and for bent push rods.When ya find the noisie one.Use a piece of hose.One end to you ear the other end to the tappet.You'll hear the loose one.The valve clearance is 0. on intake$exhuast valve.Tighten down till engine starts to miss,then back off 1/2 turn.your set.If this makes no differnce.Could be a bad lifter OR cam lob is worm.Usually its the cam. .So new cam and lifters are in order.Summit has cam &lifters priced right.A roller is going to cost ya some bucks
