MPG Discussion

[SySx]

I've seen people just in normal conversation state their mpg. I was wondering if there's any thing I can do to get close to these numbers, my truck is lifted put maybe y'all can help me. My ECM hasn't been rolled back and my Ficm isn't tuned either. Any help is appreciated.

[risco]

keep your boost below 7 psi

[rdunagan]

boost isnt the key its the rpm range. the sweet spot on these trucks are right at the 2k mark. another thing would be to get the ecm and ficm done. ive seen that help alot of guys with mpg's. those tires are robbing alot from you though. ive got 35's and it robbed about 2.5 away from me. but its hard to give up the looks for the fuel mileage back

[SySx]

I figured the tires weren't helping put the look they give is so badass.

[ironlemon]

I agree with the 2k rpm max for mileage, except for making the turbo exercise every once in a while to clean it. So the tune i have that heats the injectors or whatever is bad for milage? Where abouts do i send both the ficm and pcm for a moderate/light tune. $4.29 diesel so i really need help.

[rdunagan]

php is who i would use! Power hungry performance. they have all the knowledge about the strategies and what not and they could answer the questions better than i can. when my tax return comes in mine ficm and what not is getting shipped out

[windrunner408]

You shouldnt really see a large drop (more than 1-1.5 mpg) in fuel mileage with 35in tires. The reason you may be seeing a 2.5 mpg drop is because you havent recalibrated your speedo to read correctly for the new tire size. The bottomline is if your speedo is reading slower than you are actually going (check with a gps unit), which it would if you upped the tire size and left everything else the same, then you are going miles that your odometer isnt giving you credit for and it will look like your mileage has dropped more than it really has if at all. Check that first and see where you are. Not saying tunes dont help as they most certainly do but that your speedo needs to be right first so you can know where you are actually at.

[Karls03]

Going along those lines, are you correcting for your big tires when calculating mileage? If not here's a quick way. All that needs to be done is to find the rate of change and apply that to your mpg. So, you went from 31.5 OEM to 35.8 M/Ts, 35.8/31.5= roughly 1.13. This means that if you pump in 22 gallons and you went 237 miles, your mileage isn't 10.77, it's closer to 12.17. You simply multiply your mpg by the 1.13 rate of change.

[rdunagan]

my speedo is right on. ive checked it. ive got one of the worst strategies though so i know thats got to change to see any big difference.

[windrunner408]

Originally Posted by rdunagan

my speedo is right on. ive checked it. ive got one of the worst strategies though so i know thats got to change to see any big difference.

try a FICM tune. I have heard of 2 mpg so far with php's tune. I picked up a little over 1 mpg with IDP's FICM tune.