440 vs 360 GO!

Part of my problem is this is my first mopar lol, if you ask me about a big block ford or just about any ford i probably know it lol. The 440 does have a 727 still married to it and my 360/727 is also out of a van so they seem like they are basically the same setup just one a small block and the other a big block. The 440 has all the pulleys, brackets, etc as well so really its mostly the cost of bolting it in and the cost of a build. For now i just want the car to be a nasty little street car, but in the future I would like it to be a street/strip combo. The problem I keep tossing around is I have a big block ford in a torino that I started putting together a few years ago that gets about 5mpg and has to run non ethanal fuel due to the compression. There is not a lot of places near me for that kind of fuel so basically i need an engine that can make good power off of pump gas.