There was a real possibility that this could have been a real Merlin beater, had politics not got in the way, The original ford big-block.
The original idea was a 1650 cid V12 aero engine, aluminum block and heads, true DOHC with cams operating directly over bucket lifters. The V12 never really got off the ground, but was developed into a V8 of 1100 cid, for use in tanks during WWII. It was rated at 525 HP @ 2800 rpm, and had 1000+ ft/lb of torque from 1000 rpm throughout its operating range.
Pretty impressive stuff, IMHO.
GAA V8 modded for automotive use