The "Donovan" Hemi is the improved version of the G1 motor that was used in drag racing after the supply of buildable cores were gone. Seems like Donovan was one of the engineers who worked on the original motor at Chrysler? The most-desired OEM G1 Hemi was the 392, of course.
The "Keith Black" Hemi is the 426-style Hemi.
Interesting in that any motor with center spark plugs (from the top) was deemed "Hemi" and "CHRYSLER", in the race results. Except for the Ford 427 "Cammer" DOHC motor.
CBODY67