PHP fuel mileage

[slimsantalol]

Hey guys, a while back I got the pheonix 6-pos chip from php and put it in my 97 f250 5spd. the tunes i got were 1100 rpm idle, stock, 40hp tow (up to 12.5k lbs), 80 hp eco, 100hp perf, 140hp extreme. when running stock tune, i was getting 16 ish mpg. ever since using the 80hp eco im only getting mid 14s. i have waited a while to bring this up just in case it was too to playing with the extra power. well im not playing with it anymore and i even did a 100% highway test. still 14s. but when i towed a 10k lb load, i did 19 in the tow tune.... anyone got any ideas??

[ol_Blue97]

Your higher HP tunes will give u the best MPG if u keep your foot out of it.

[BigFuel]

^ x2. But I can't keep my foot out of it, just too much fun.

[terryknight]

drive in the tow tune.

[slimsantalol]

i get that the higher hp tunes give the best mileage depending on how i drive, but why would the economy tune give me so much worse mpg? i also forgot to mention that the economy tune also doesn't seem to like low rpm. Engaging the clutch requires me to spin it up to 1100+ or the thing hops and kicks like its trying to stall on me. And if im already rolling and try to give it a little throttle it does the same. this happens til around 1300 rpm. is there any chance that maybe whoever wrote the tunes had accidentally misstyped a value somewhere?

[BigFuel]

The Eco tune is not for around town driving. It's not even a set-it-and-forget-it tune. You only use it for long freeway driving when your speed and RPMs are constant. I.E. you get on the freeway for a 30 minute drive to work, set the cruise control, turn the dial to Eco till you get off the freeway.

Side note, these engines don't really like to see the shy side of 1500 RPMs unless you are unloaded and slow speed cruising. Unlike newer diesels our turbos don't start working well until 1800 RPMs. If you like running low in the RPMs look into installing a 1.0 turbine housing.

[slimsantalol]

i run low rpms cuz im lazy and dont wanna do the extra shifting if i dont have to. also saving the clutch from just a bit of extra wear. Most of the time i do run unloaded and i have 4:10 gears. And i have done full highway tests. On stock i did an interstate trip and got 19.2 mpg. I did the exact same trip on the eco tune with just about the same trafiic, only to get the same 14 mpg... thats horrible! actually, if im not mistaken, that may have been down to the high 13s.

[BigFuel]

Ok, I'll succeed that it may be in the tunes.

[slimsantalol]

damn, i was hoping i didnt have to send it back. =(

[AddictedOffroad]

Originally Posted by BigFuel

The Eco tune is not for around town driving. It's not even a set-it-and-forget-it tune. You only use it for long freeway driving when your speed and RPMs are constant. I.E. you get on the freeway for a 30 minute drive to work, set the cruise control, turn the dial to Eco till you get off the freeway.

Why do they call it a daily driver/economy tune then?