Not Ranked
Excaliber mentioned the lifters spinning--absolutely gotta spin--if you have any doubts, take off the valve covers and run the engine to see that they all spin as it runs--yeh, I know the lifters are hard to see but the push rods will spin with them--
Another caution--we do a lot of the earlier muscle/classic type engine rebuilds and started using another shop for thermal cleaning some of the rust bucket cores--this process uses high temp to burn all the oily crud and then a shot blast process to knock off the residue--looks super, block is ready to paint--BUT--bolt holts need to be retapped and the LIFTER BORES ALL HAVE A SHOT DIMPLED SURFACE that makes the lifters tight in the bores--requiring at the minimun a bottle brush ball home treatment up to actually rehoning the surbace with a lifter honing unit--the lifters absolutly have to be free
All flat tappet (solid or hyd) cams are ground at a slight angle toward the back that causes the cam to want to run rearward in the block which keeps the timing gear against the block surface in the front(this angle is also what spins the lifter) Roller cams ARE NOT ground this way and need a thrust plate to locate them in the block. I often wonder if maybe some of the cam grinders haven't ground some cams without this angle which would result in premature failure. The lifters should also have a very slight crown on them and not be worn flat or concave.
Jerry
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