I have put 3 tanks through the IDI. They have been 9.0, 9.4 and 9.2 MPG. The V10 being used the same way, at the same speed, on the same roads gets 10+ MPGs on fuel thats $.30 a gallon cheaper! It also makes 100 more HP and 100 more TQ. Whats the deal? I thought these IDIs got much better fuel mileage than gassers.

 

Don't know how it compares but we got 18 mpg on a trip last weekend with our clunker. There with 2 people and tools. On the way back with same and dana 50 front end/springs and rear axle and some misc. parts.

What is real crazy is I believe ours has the original injectors/pumps, etc. just looking over how bad everything looks on this truck and talking with the previous owner who got it off a ranch as a work truck.

A typical load on a trip averaging 50-60mph for us, mostly on flat freeway has shown a consistant 12-13 mpg. That is with a 5,500 pound 24 ft. hitch mounted travel trailer, people inside the cab, tools and 2 sportbikes in the bed.

We have abused axles and just picked up a cheap set with 4.11 gears, some say I am crazy to change but we don't daily drive in it and would gladly exchange some mileage for towing help. Our setup maintains on flat ground just fine as is but the hills kill the poor truck.

 

while the v10 is assbackwards from an IDI, many things come into play with the IDI which I have also learned myself in the last few days, you might want to check out my postings, do a search for "How to increase mpg" in IDI forum, gearing, IP and injector wear, dually or srw,lots of idling, stop and go or highway?

edit: for example my truck setup I have learned it is normal to recieve about 14mpg I am in the process of thinking how to switch out the 4:10 to 3:55

 

ZF 5 with 3.55s. New IP and injectors, new motor has 900 miles on it.
SRW flat bed that weighs 8,000 empty. Some empty city and highway, a little idling, and some hualing in light hills.

 

hmm sounds like you have a nice setup, I envy you guys with the zf5, but anyways how about your Injection pump timing? when you installed it did you have it timed properly? honestly I just did my timing on the truck recently and it increased my mpg about 2mpg, my trucks timing was retarded to much so I advanced it, also you havent tinkered with the fuel screw on the IP correct? because I have learned that aswell eats mpg

 

Its set by ear and the pump is up a 1/2 a flat.

 

take it to a shop and have it timed ellcheapo

 

Its pretty close the way it is.

 

Time the v-10 by ear and then compare the two. Not sure how you could be sure the timing is "pretty close" if its set by ear,I think what Joe f350 said is the obvious first step in figuring it out after the injector and pump install.
nate

 

It sounds like it should, but I get your point. Thing is its a 3 hour drive one way, plus the $100 to have it done. Thats a whole day and close to $200 with fuel to have that done.

 

For that cost alone is enough reason to shop around for the diesel timing adapter and time it yourself. Then you could help out with timing anyone else in your area and make a dolllar back.

 

That sucks.

 

ouch.that would make me cry.
how many miles on this rebuilt engine now Bill?

is it this rig here:
https://www.ford-trucks.com/forums/p...ictureid=19731

is that a f250 or 350?
is it 2 or 4wd?
did you inspect the front wheel bearings,and insure all 4 wheels spin freely when you jack them off the ground?
when's the last time the trans/transfer/rear oil was changed?

timing an engine by ear is good enough to drive it to the shop and thats it imho.
fuel costs to much to play horse shoes and grenade games with engine tuning theses days.

 

He posted 900 miles. A far cry from broken in and way to early to even consider fuel milages on any engine IMO.

 

Little over 900.
EDIT: haha, you posted while I was typing 87crew.