What should I do for Better Fuel Economy?

[nicksorenson]

Are there easy things I can do to improve my 94TurboIDI E4OD's fuel economy?
Also, on power... I'm assuming I'm limited (when I get my guages) to certain low amount of boost and fuel by EGT's. If I do any simple mods to help this what are they?

Intercooler?
Water/Methanol?


Which is easier/better?
Anything else I'm missing?
Thanks!
Nick

 

[BROWNIEBOY525]

theres a few things that you can do to improve fuel economy the biggest is going to be driving style. if you drive with a light foot your milage will be good if you take off like your drag racing its going down.
you can open up the turbo outlet, downpipe ,and exhaust.
how many miles are on the truck? you could be do for a new ip and injectors
the max boost the you want to make is about 12psi anything about with out head studs and you heads will be taking lift off.

 

[Dirtleg]

Intercooler will improve air density(more Oxygen). Yes that will help.
Free flowing exhaust will allow turbine to spool faster making compressor move more air so that will help too.
Getting the least restrictive path for cool air to reach the compressor would be the other simple means of getting more air in the engine. Hot air from the engine compartment does have a negative effect on air density.

More air(oxygen) during combustion means you can burn more fuel without murdering your EGT's and will give you more gases for expansion to spin the turbine faster meaning more boost. It's not a perfect world out there and turbine and compressor inefficiences come into play somewhere along the way and you reach a point of diminishing returns. Essentially higher EGT's without additional boost or power/torque. But there should be significant room for improvement before you reach that point.

 

[tonkadoctor]

Tape a raw egg to the gas pedal and don't break it. It's the cheapest and single biggest improvement to fuel economy you can make.

 

[nicksorenson]

I got 12.8 or so MPG last run and I really was not driving excessively. Not like a little old lady but not like a 16 year old by any means. I drive my 6.2 detroit diesel Suburban with a much heavier foot (I have to to get it up hills or even to move forward for that matter and I routinely get above 20+MPG and that thing is old, worn out with 260k and bad compression. But it runs good and easilly gets 20+ MPG. I'd think with an easy foot I should do better than 12.8 in the 7.3IDI.

 

[haywire]

open up the exhaust, get rid of ford's smashed sorry excuse for a down pipe.
also ram air and or a free flowing filter would proboably help. what shape is the tranny in? if it's worn, excess slippage will bring your milage down too. what's your gear ratio? i've got 2 idi's one with 4.10's and one with 3.55's. around town and on the farm the one with 4.10's actually gets better milage(maybey cause it's the 166hp engine, the other is 185), but on the highway the one with 3.55's consistently gets 2 to 3 mpg more than the one with 4.10's.

 

[tonkadoctor]

I got 12.8 or so MPG last run and I really was not driving excessively. Not like a little old lady but not like a 16 year old by any means. I drive my 6.2 detroit diesel Suburban with a much heavier foot (I have to to get it up hills or even to move forward for that matter and I routinely get above 20+MPG and that thing is old, worn out with 260k and bad compression. But it runs good and easilly gets 20+ MPG. I'd think with an easy foot I should do better than 12.8 in the 7.3IDI.

Yes you should get better than 12.8 with the IDI. Mine would do 18 empty with the 4.10 gears and got a record of almost 23 with the 3.08 gears I swapped in..... empty, interstate driving about 62 mph.

Have you had the timing checked. Diesels are extreemely sensitive to small changes in timing.

 

[Cat_Rebel]

I get about 14 when I'm ******* it & as much as 17 when I baby it. Alot of that is 35mph town driving too. I know it needs a tranny flush so who knows, that may help out too. I have a straight pipe, soup bowl delete & the pump turned up.

 

[icanfixall]

If as posted you still have the flattened out down pipe just off the turbo you need to upgrade to the better flowing kind. Then remove the muffler. Thats probably the original too and its usually full of soot by now. These motors that have a turbo run really quite when you remove the muffler. This is because the sound (some call it noise) is chopped up by the turbo that is spinning around 130,000 rpm. Yes, they will get louder when you really get on it but thats when you would expect to here it. Ever listen to a diesel pulling a grade? They make more noise because they are "working". Boost, pyro and a real coolant temp gage are needed so you don't kill the motor making any changes.

 

[Full Monte]

Driving style
Do 55 mph on the highway to cut down wind resistance
Gear Ratio ...may need an overdrive unit
Get it set up so you can cruise at about 1600 rpm on the freeway
Skinnier tires, get rid of the knobby rock crawlers...put on highway tires
Get the timing set correctly
Replace the tailgate with a mesh-type. Myth Busters did a program on this one.

 

[nicksorenson]

Do I need a Pyro if I just change the exhaust system?

 

[creighta]

myth busters found that the tailgate should be left shut for better MPG.

I say Gear ratio and good habits are the big two for mpg. my 7.3 NA w/ 3.73s gets 13.8 around town and as good as 17 hwy

 

[Cat_Rebel]

Do 55 mph on the highway to cut down wind resistance

Around here the speed limit is 70, if you do 55 you'll get rear ended by a semi. I'd rather play buy the rules of the road then to compromise my personal safety.

Replace the tailgate with a mesh-type. Myth Busters did a program on this one.

Actually they found that you get the best MPG when you have the stock tailgate up.

 

[kcw12]

the myth busters did it with the tailgate down, but not removed. I got better milage when i had a mesh type gate, but they didnt last long with me and i didnt use them anymore. To get better milage out of and IDI

1. Make sure IP is good
2. Make sure Injectors is good
3. Make sure motor is correctly timed
4. Make sure you have a CLEAN air cleaner
5. Make sure that you dont have the flat downpipe
6. Remove muffler
7. Remove 4.10s for 3.73s or 3.55s ( i like 3.73s)
8. Tallest lightest tire possible
9. and a few things that i forgot.

 

[haywire]

Do I need a Pyro if I just change the exhaust system?

shouldn't need a pyro lest ya put more fuel to it.