That's because they came with nanner groove shafts. The failures you see most often are with those rockers put on hydraulic shafts with no nanner grooves AND they also have too much spring pressure. Put those two together and they'll burn up every time. Used how Chrysler designed them and they're dang near indestructible. Especially when they are modded to accept high quality adjusters, like those Mancini rocker arms posted up there ^^^^ those are nice.
