fatherof4

i have an 89 short bed, 2 wheel drive, 350 tbi, 700r4 (recetnly rebuilt with a medium shift kit), not real sure of the gears in the rear end their isnt a tag on it. i am looking to rebuild the motor this sumer and just looking for a little guidence. my goal is to get good gas mialage and still beable to have some go to it. so far what i have gathered from other posts is that tbi isnt a bad thing. i dont want to have to change alot of things as far as wireing and comp. i do understand that i can get a chip for it that will help with all this.

also wandering if heders and no cat will hurt milage. rite now i am getting 15 mpg with no cat. i have done all the tune up i can. cap, rotor, wires, plugs, oil & filter, air filter, thermostat, EGR, fuel filter, new tank and pump, knock sensor, little taller than stock tires (just throws off the odometer 2.5 miles every 100). truck has just under 300,000 and motor has around 100,000.

this truck is very inprotant to me. if anybody could give me any guidence that would be great. thank you