Not to hijack too badly, but......
Hylift Johnson A-2011R lifters, reboxed by Comp.
The failure here is the result of a loss of valvetrain control.
The pushrods are dancing/jumping around on the pushrod cup, they land on the thin sheet metal retainer, which collapses from the point loading, then is no longer able to retain the piston assy.
Normally when this happens, the retainers are riding around on the pushrods.
But when you encounter severe instability, I’ve seen them unbroken, but laying in the valley....... so the “float” was severe enough to let the retainer escape out from under the pushrod while it was jumping around.
The propose of that specific style of retainer is to preload the piston assy, so that no additional preload is necessary, while reducing the volume of oil in the piston assy...... which means the lifters can’t “pump up” and hang the valves open when “float” is encountered.
If you don’t run the valvetrain into pretty hard float, they hold up “okay”.
If you float them hard, and the pushrods start dancing around, the thin metal retainers are a little frail, and you end up with the scenario in the pic.
Now...... back to your regularly scheduled UTG build review.
View attachment 1715539362
If you removed the thin steel retainer and installed a regular tru-arc style of snap ring in those lifters, they would be fine.