My 422 smallblock build

"Chrysler's use a bigger diameter core than Chevrolet. That means for the same lift, the Chrylser will have a higher wheel speed."
you thinking rpm with the larger wheel YR?
AFIK all retrofit hr use the .700 wheel
What's oem mopar hr?
you can fit a .815-820 in a.904 lifter bore oo big get too narrow
or bore to .937 to clean up the lifter bores
with keyed lifters even larger
I've used isky's