Back up the bus, Gus. First prove the theory.
What are you torquing those bolts down to?What kind of spring pressures are you running? And what arm-ratio?, And what wall thickness?
Remember, I put mine on as a prevention, cuz I like to run pressure, cuz I like the valves to close when the cam tells 'em to. Especially at 7000plus rpm.I hate lifter pump-up. And with a 4spd,no rev limiter(cheapskate-broke actually), and a factory type shifter, missed shifts are fairly common.And so I do everything possible to prevent it. Within reason.
But ok, mine are blue-anodized aluminum anvils, and I bought them out of the Mopar Performance catalog about 15 years ago.I have no idea who manufactured them.