fuel economy help

[burganyntan98]

I have a 98 ecsb w/ a 305 in it. ive been doing almost any mod i can think of to get my fuel econ up. cai, exhaust (no muffler just cat) electric fan, basic tune up. and no matter how i drive or where i drive it tends to get the same fuel economy as i did before any of the mods (15 mpg/avg). i have a feeling it has something to do w/ 02 sensors. any help or ideas on what else i could do to it in conjunction to tuning the ecu would be greatly appreciated. im looking to get around 20mpg on the hwy.

 

[ndians68]

gears

 

[Playare]

Gears and a tune. Don't expect too much, these trucks love the gas.

 

[MOBS]

When did you last have your injectors cleaned/inspected, they may be failing on you. If nothing were wrong with the engine, I'd say too low of gears also, or driving habit. If you're using it as a tow vehicle, then I'd just deal with the lower gears. Only other way would be with a 2-speed read end haha. Kidding aside, I vote gear change. What gears do you have anyways?

 

[burganyntan98]

im pretty sure its just a 3.42 just a half ton 2wd. i rarely use it to tow more than a fourwheeler or two. but it has seen a tractor and a few f250s. lol. i do a pretty even amount of highway and city driving. i could understand going lower gearing in the city like a 4.11 or so, but wouldn't higher gearing like a 3.08 be more efficient on the highway? the injectors were cleaned around may. engine has never cut out or had any lack of power. so id imagine the injectors would be alright.

 

[am92]

A good tune should get you 1.5-2 mpg. I'd say 3.42s are a pretty good compromise for mixed hwy/city driving. 17mpg mixed is about as high as you can expect...