Something that makes me laugh is how all the flathead Ford guys slag the dodge/ply six. They don't overheat. They have both mechanical and vacum advance. Hardened valve seats Modern oil pump And take a .450 lift cam without any head mods. Your dodge 251 made 100 hp and 220 ft/lbs with the horrible mil spec governed carb. With a good dual intake,header, cam and some more compression it will eat a Ford flattys lunch. And still get about 20 or so miles per gallon.