Leon has it right. There is nothing wrong with the valves or the lash caps. What IS wrong is something in the valvetrain.

Now while it could be too much spring pressure, it could also be too little for how aggressive the intake lobe is and could actually be trying to "throw" the lifter off the cam......OR it falls out from under the lifter on the backside. This beats the hell out of valvetrain parts. How MUCH lift is of little consequence, it's how aggressive the lobe is.

We have guys on Drag Week with cams over an inch of lift and they live just fine. I just have to slow the lobes down and set the parts up right.

HEMI valvetrain is inherently bad already. Mismatched parts make it horrible