I'm still in the air over an engine for my f100. I want to do something a little different like and old Y block or a 300 six, thats the WANT. But the NEED is good fuel mileage as this will be a daily driver, I know fuel mileage and tradtional does not go hand in hand but if gas prices go to 5$ a gallon, a lot of cars are gonna be sitting parked in garages. I have considered a four banger but really don't want to go that route or to diesel. Goal is to build the truck light as possible, maybe do some sectioning and chopping to reduce resistance. I will gear it tall with some 3.27's and and around a .67 OD. Pretty much a typical mustang drivetrain. This part is O/T but several of my stang friends are getting 25mpg's out of their 4.6L. This is causing me to seriously think about going to a carb'd version of one these. Not to mention how much lighter the aluminum block is. Curb weight of a mustang and 56 f100 are close at around 3200. Any other suggestions or setups for mpg on ford engines???