1968 Barracuda w.73 Charger 440 RB CAM MOD
I always thought the compression distance was the killer in the later motors. There are a handful of off the shelf cam replacements that can give you a lopey idle or change the powerband to a different rpm range. Things to consider are spring pressure rates on new cam(if you can use stock springs) , condition of existing cam bearings and timing gears. By that year it is nylon covered cam gear that gets shitty and brittle.( I found all the nylon in the pan of my 77 440 ) you also need new lifters.