I'm. Helping my buddy put togeather his ot car with a 440 mopar and he has cast iron heads and just bought a set of harlon sharp roller rockers. We installed them with some push rods that we had and at full lift the roller seems too close the edge of the valve. Is this something that can be changed with push rod legth or would we need to shim or machine the shaft mounting surface to fix? I will post some pics when I get to my computer.
Here are the pics. I think to fix the problem the valve needs to be shorter or the mount for the rocker shaft needs to be machined down.
I believe you think right and maybe a combo of both.., to check back off the adjuster enough turns to color the end of the valve with magic marker, reset clearence [same turns] and run thru cycle, back off adj and veiw stem..should have a mark around 1/16 wide and of course be in the center of valve..Those heads have the cast in and machined stands for the rocker arm shafts? I think someone makes a kit to mill off the stands and replace with alum stands, maybe Indy Heads...
If I'm seeing your picture right, it looks like the roller is too far outboard. That means the valve is already effectively too short. A simple fix would be to install some lash caps and then shim up the shafts as needed/if needed. Depending on how much you needed to shim, slightly longer pushrods may also be needed to keep the pushrod cup in the proper position(for oiling)
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