so in the build plans for my 1978 f150 4x4 ive been thinking about engine performance ive decided rather than rebuilding my 400v8 (ive learned some die hards get mad if you say 400m lol) ive been thinking why not use some of fords more modern ideas ie. ecoboost. what im thinking is use a 302 (im told a pre 1974 engine is preferable not sure why though if someone could shed some light on this) a tbi conversion for tunning reasons and forced induction i undecided on turbo or supercharger yet. the hope is to have an engine powerfull enough to move the truck on 35's with 4.10's about as well as the 400 moves it on 31's with i think 3.73 diffs (in 4th it redlines at 130kph standerd trans) but get decent mileage 17+mpg would be nice if its possible

 

Forget the 17 + mpg , I have a short bed f-100 , 2 wheel drive ,with a stock 302 , 3 speed column shift with 3:25 gears and it only gets about 13 or 14 mpg. I's hard to push a brick and get good mpg , they were never built for it. But ,if you do i will follow along and see if i can pick up some ideas for more power and more mpg. Good luck.