Maximum Lash Ramp Rate?

That is a lot to put up with RF! That is poor manufacturing work.

Yeah, the problems seem to be getting gradually worse. The hydraulics I have are showing excessive leak-down on some of them. You stop the engine, wait 5 minutes and 1-2 of them will leak down all the way if they stopped with their valve open. And 1 of those will not pump up.

They are regrinds on the bodies, which I have no problem with, but I think whoever is doing them is not properly matching the plunger OD to the body ID at re-assembly. That clearance is all over the map from .0001" to .0010" or a bit more, out of a set of 8. I found an old book reference where they talked about sorting the plungers into size bins by plunger OD, and then matching the plunger and body to keep a clearance around .0003". It is on page 87 here: Big-Block Chevy Performance

So that is the frustration. I think that a lot of the knowledge in these parts has been lost or thrown out as time has gone by and the prior generation of manufacturers has departed the scene.