Thanks Im well aware of the 4bt I just really want the 6bt. Call me crazy but ive been able to find more 6bt's and at a cheaper price than 4bt's. I know the whole point of this thread was MPG's but I still want some power too. Everyone keeps saying a 4bt will be enough power but im not convinced. Yes I know they haul around delivery vans and such but have you ever driven one of those things? If I was doing a Ranger or half ton then yes I would entertain a 4bt, but for a 3/4 ton truck, I really feel the dirty dozen is the way to go. Maybe I'm wrong? Plus I think it will be easier to get parts later on if im using a dodge 12 valve, dodge clutch, dodge trans, etc. Even though I know alot of parts are interchangable. Im assuming to make the same power as a 6bt with a 4bt i'd have to increase fueling, which would decrease economy. A modded 4bt to achieve the same power as a stock 6bt would probably get around the same economy right?