20 mpg hijack thread

[bojak]

i did not want to hijak a thread so i am starting this one. I have 89 v3500 with 5.7 tbi and 4:11 gears,d60 up front. It is running 285/75/r16. i plan on lifting it 2.5". This is a runaround truck not a heavy hauler.

What i was wanting is some recomendations on building / modifying my drive train for optimal fuel economy. I am not shooting for 20mpg, just a better mpg for moderate changes. From what i understand a LS motor is the ticket but i was looking more for improveing what i got. Stay TBI, convert to carb? Cahnge gearing? what size? What exhaust intake setup? Any ideas are appreciated.