more power = better fuel economy?

[RLDSL]

Where in arkansas are you located? I'm down near cape girardeau, missouri. Not far from the AR border. I can bring a 6 pack for your troubles at least!

I'm about 30 minutes or so out of Little Rock around where hwy 60 crosses the Arkansas River at Toadsuck ( just outside of Conway ) roughly where US 65 and I 40 come together

 

[oldblue05]

fwiw I made a 600 mile round trip thurs, got 13mpg on the first leg passin everything in sight, then 19 mpg comming back going right around 70 with A/C on the whole time of course, mods are in my sig.

 

[93_444idi]

I make trips down to memphis junkyarding sometimes, I could take I-40 over. But I was just thinking about it, I've got another idi I'm wanting to build up and put in. It wouldn't make much sense to time this one when it'll be out in a couple months. I may take you up on your offer after the other one is in though!

 

[rjjp]

That's true, up to a point. The majority of it has to do with efficiency. The more efficient the engine can do it's job and get heavy trucks up to speed, the less fuel it's gonna drink.

Seems to be the truest point in this thread...
Adding a turbo increases the volumetric efficiency.
The synthetic lubricants increase the mechanical efficiency.
Proper timing increases the (C.R.S. is kicking in here) efficiency.
All of this and more will increase the fuel efficiency, our engines are big enough for our trucks, but by increasing the efficiency of everything you will increase fuel economy.
Porting and polishing will increase the volumetric efficiency.

Basically anything you do to increase the power besides adjusting the fuel pump will increase your fuel economy, some adjustments to the pump will increase your fuel economy, but that is a double edged sword.