[Walt Dupont--Me.]

Originally Posted by Brian

Pete said-"When using stock Ford lifters be sure they are the hollow STEEL ones with the two 5/32 holes in the side, NOT the cast iron ones with the elongated slots."
Why? Surely they are fine to use in the original application, ie, with mushroom bottomed valve stems. In my experience, having pulled down untold of these engines in all conditions, I've found the cast iron type, as fitted in the earlier motors, to exhibit less wear than the steel ones. The steel ones tend to get a hammered in depresion from the valve stem constantly hitting, and the bottom face, that is in contact with the lobe, tends to wear hollow, moreso than the cast iron units.
Walt, the Australian manufacturer of the worlds finest adjustables, is Mike Davidson, aka Flatattack. Rather than using a 3/8 fine thread bolt as the means of adjusting, he has designed his lifters to use about a 7/8" thread. Much sturdier, and the heat treatment is spot on!

I have found more than one of the early cast iron lifters broken, the cast between the slotes is pretty brittle. Walt