Mopar 318/275 HP vs. Chevy 327/275 HP 'L-30'
In 1966 Mopar did build-test a 300 Cubic Inch LA Engine
for Modified Speed Boat Drag Racing.
It was a 'sleeved' 273 with a 3.80" Bore, with specially modified
Cylinder Heads, with bigger Valves.
Unfortunately there was very little released information.