273's for the Dodge and Plymouth are the same except for the 4bbls where they got different stickers on the chrome air cleaner; Charger 273 for Dodge and Commando 273 for Plymouth. Some of what you are seeing are aftermarket aluminum intakes (primarily Edelbrock) but "Dodge Parts" are not aftermarket.... Hell, my 66 Barracuda 273 4bbl came with a Charger 273 Air Cleaner...at delivery. Not unusual as it was made on the same line with Darts at Hamtramck/Dodge Main