Pictures, a link, whatever you like. Some proof of this statement you made in post #52: The shaft MUST have grooves for hyd lifters [ capital letters in original ].
Let’s see. Decades of taking apart engines that had hydraulic lifters and scored shafts and rockers. Fixing all that and grooving the shafts and not one ever failed again.
IIRC in 68 when the 273 went to hydraulic lifters the shafts were grooved.
It’s amazing the **** you will argue about. Looks the OP’s pictures. It’s not that the Chinese bushings are soft because a 273 rocker will do the same thing without a groove in the shaft.
W2 rockers came in unbushed and bushed. For hit RPM you had to use the bused rocker because the unbushed rocker would grab the shaft no matter what you did. And all those shafts are grooved.
