The 1974 360 Challengers and Cudas and the 74 through 76 360 Dart Sports and Dusters ran better than the 1973 340 cars of the same weight.
Yes 318willrun my 360 came out of a 75 C body and is now 416 inches and is in my Dart and does have enough meat to go to a 4.100 + bore, same as a 340.