Need Some Advice

[Blown03HD]

Ok guys heres the run down first,
2006 F250 ccsb, 3.73 rear end, 6 inch lift on 37's
Studded, egr delete, egr cooler blocked off, MBRP dual exhaust no cat. K&N air intake

Powermaxx turbo, airdog II, Vivan tune (looney), stock injectors

I've had Vivan re-due the tune 3 times due to turbo lag and shuttering at low rpm. (by the way great service) and it is running very well at this time.

Here is my question....

From what I am reading, there is a little turbo lag with the Powermaxx and I will have to except that. But What I am having trouble living with is the POOR mileage. I have not done any highway with the truck since I bought it due to where I live and most of my driving is city. But in the future it will be city 70% highway 30%. Quick hand calculations with all the above is around 10 mpg. I am correcting for the rolling mass of the tires when I do hand calcuations.

Any ideas why my mileage is so bad? Are the tires too big for the gears? Is the airdog II just dumping too much fuel? Does the FICM hurt mileage? Is my Colorado 5500 ft altitude hurting mileage....PLEASE HELP!

[dr8082]

You can read my mods in my sig, and im running 3.73s. On the high way, even in the mountains i get 16 to 17. Around town im gettin around 14 but that also depends on my foot.

[Blown03HD]

I am purposely driving it like a grandma, every once in a while giving it beans. Was that post to make me jealous about my mileage?

[dr8082]

No not at all, something is deff not right with your mileage thats all i meant. Have you tried going back to stock and see if there is a difference?

[Blown03HD]

Yea when I bought the truck it has a bad tune it in but the truck returned 13.5 at best during my 1200 mile drive home. Put the stock tune in and contacted Vivan. The truck was doing the same 10 mpg city with the stock tune.

[dr8082]

I was only trying to give you a comparable, 6.0s are better on gas than my 7.3 plus i have 8" lift and 40s so you should be killin me on mileage. I dont think the elevation has that much to do with it. A buddy who has an 04 and i went to the mountains at chistmas and he got better mileage than i did, he had 6" and not sure about his tires.

Sorry i couldnt help.

[dr8082]

It might be too late for alot of responce tonight but i bet the 6.0 guys will chime in 2maro and help ya out.

[Blown03HD]

I appreciate it, i'm hoping someone has some idea on what to do

[xjeeper]

Ficm will effect mpg, I get 12 in town on winter fuel on 35"s, high teens hwy @ 75 (sometimes 0ver 20 mpg) wind and fuel quality and tempurature all impact mpg. My PHP FICM tune was worth 1-2 mpg over a later flash.

[TooMuch03]

What do you mean by correcting for the rolling mass of the tire? Is your speedo (ad therefore your odometer) recalibrated for the larger tire?