Fuel Mileage

[Diesel JD]

Best bet is to tune the engine for a lot of power within reason and then not stick your foot in it too much. You want your injectors matched to within 100 psi of each other 50 would be better but getting there is pretty tough. I'd say 1800psi would be about minimum for a good injector. Then you want to time the injection pump to about 9.5*BTDC with the pulse method or 0-3.5*ATDC with the luminosity method depending on cetane ratings or if you're using a fuel cocktail. WMO and low cetane fuels should have more retarded timing, higher cetane fuels like biodiesel should have more advanced timing, closer to 0*. I run B100 and am around 2-2.5 ATDC...I could probably advance it some more but it's fairly clattery where it is.

 

[DontKnowJack]

New IP and BB's...getting 10 solid around Delaware county (local stop and go) with a super light foot. I should be mid teens like several years ago...original Tranny/C6 TC maybe be slipping some
Aired up tires to max (80) to experiment...made no difference...dropped psi to 65 front 60 rear.

Wow! I've been considering a Baby Moose and new BB's but having second thoughts seeing that you're only getting 10. I get 11. I have good intake and exhaust. Not sure what to try next.

 

[HammerDown]

Wow! I've been considering a Baby Moose and new BB's but having second thoughts seeing that you're only getting 10. I get 11. I have good intake and exhaust. Not sure what to try next.

I'm very bummed about the lousy mileage ...I can't believe it's the baby moose but question one or a few of the 'new BB's' that came from Pensacola diesel...could be lousy spray patterns

 

[DontKnowJack]

I was assuming that since you had a baby moose that you got your bb's from Mel as well. That's what I was considering.

I got a pump from Pensacola Diesel 2 yrs ago. Big mistake. Took it to a pro diesel mechanic after I couldn't get it running. It wasn't even pumping! He took it to a pump shop and they discovered parts were put in backwards. Total cost $1200. The pro mechanic called Pensacola Diesel when he realized it wasn't pumping. They told him they had checked it and it was pumping. Told him he didn't know what he was doing. He asked what I wanted to do after he hung up on the guy. I told him to just fix it.

 

[Diesel JD]

I'm very bummed about the lousy mileage ...I can't believe it's the baby moose but question one or a few of the 'new BB's' that came from Pensacola diesel...could be lousy spray patterns

Ray, did you get the Pensacola ones pop tested before you put them in? In my box of Pensacola "remans" I had 2 or 3 nice ones and a couple acceptable injectors but about half of them were ******* that popped lower than 1800 and had no spray pattern at all.

 

[3/4 Ton-O-Fun]

So who sells the cheapest matched set of injectors?

Who is a good reman shop for all our old diesel needs?

 

[FORDF250HDXLT]

Then you want to time the injection pump to about 9.5*BTDC with the pulse method or 0-3.5*ATDC with the luminosity method depending on cetane ratings or if you're using a fuel cocktail..

fully up to operating temp ( stock motorcraft t-stat fully open @ 212 degrees or just after a good load up around 220-237 is good) @ 1400 rpm; 4-7 ATDC depending on cetane and altitude actually.

3 would be very advanced,and 0 would be extremely advanced,off the charts.she'd probably be real ******* engine components (that's if you could actually live with the horribly loud rattling going down the road.i once advanced to 3 with mine on 40 cetane fuel...............it didn't sound very good lol.)

http://arrc.epnet.com/autoapp/8978/8978CH05_INJECTION_TIMING.htm

'93 f250HD 7.3l NA/E40D/3:55's with 225's for 3.84 actual gearing (w/ odo correctly re-calibrated for the shorter tires)/DRW conversion/8'W X 9'L enclosed stake body dump weighing in @ 8100 lbs empty.
engine timing set @ 6 degrees ATDC with fuel cetane value range of 38-42.

hauling 1-3 ton regularly and towing 1 ton chipper often.
top speeds of 45 mph and taking off so slow id put granny to sleep most of the time.applying the basic hypermiller tips such as starting out with ease,coasting to stops,bleeding off the hills,steady foot that makes cruise control look outright horrible,etc.

lots of rural driving this combo on what most would consider back,curvy,hilly roads up here in Maine with a max of 1.5 hr trips at a time.most of the time 30-45 min trips with lots of stop and go.
think old horse and buggy copy cat roads.nothing planned like out west.



fuel economy mods so far;
cowl induction with soup bowl removed.
synthetic engine oil.
synthetic blend rear diff oil.
custom single exhaust starting with a free flowing,true custom built Y pipe.not that stock T pipe.
smoothed stake body sides.
electric engine fans.not set to kick on until well after the T-stats full open temp.
mostly hang around 225-235 degrees.no higher than 240.
culvert for tool holder/aero mod above cab.
standard IDI tune up w/ delphi BB codes and IP from U-Haul inventory close out.


at time of this post:
14.46 MPG over the course of 59 tanks.of which most are consecutive fill ups for a VERY accurate true average mile per gallon.would be higher today had i fixed a rear wheel tire issue much sooner than i did.
non of those "high peak" numbers while driving like a car from me.
(snow plowing not included of course.)


http://www.ford-trucks.com/forums/garage.php?do=showfillups&vehicleid=1301

 

[FordGuy100]

Thats insane showing the drop in mileage over time! Probably as IP and injectors wear, but that chart definatly shows a slight decline of mileage.

 

[FORDF250HDXLT]

Thats insane showing the drop in mileage over time! Probably as IP and injectors wear, but that chart definatly shows a slight decline of mileage.

yes.thats due to couple things.
1.i was SRW at the start.DRW conversion took 1.5-2mpg away.
2.i had a DRW issue that got progressively worse. that took far too long for me to resolve.that's now fixed,and now i can peak 17 mpg when empty (though very rare) when not using the A/C.
i just had the rare occasion of running empty,had the A/C on full tank and nailed 15 exactly.
still in the progress of further aerodynamic mods now as well.
been working hard lately to get the DRW conversion hit gained back,and hopefully perhaps even surpassed,but i think a turbo is the only way to accomplish this.

 

[Diesel JD]

fully up to operating temp ( stock motorcraft t-stat fully open @ 212 degrees or just after a good load up around 220-237 is good) @ 1400 rpm; 4-7 ATDC depending on cetane and altitude actually.

3 would be very advanced,and 0 would be extremely advanced,off the charts.she'd probably be real ******* engine components (that's if you could actually live with the horribly loud rattling going down the road.i once advanced to 3 with mine on 40 cetane fuel...............it didn't sound very good lol.)

http://arrc.epnet.com/autoapp/8978/8978CH05_INJECTION_TIMING.htm

You and I are just never going to agree about this luminosity timing issue. Maybe for your tools and your fuel this is ok, but for my fuel and my tools 2.5 ATDC is not too far advanced. 5ATDC by my meter sounds like a fuel injected gas engine almost. Sure it isn't supposed to be threatening to lose it's lunch but it needs to sound like a diesel and many people are afraid of normal clatter. I have no doubt that with 40 or less Cetane, the storyw ould be different, then you'd need to be in the 3-5 range. The homebrew biodiesel I make, I assume a cetane value of 47 and up. Also consider how old that chart might be...the fuel when our luminosity meters were built was HSD which had lower cetane and higher heating values. On the other hand if you have this chart and it matches your experience, then use it. As for me, I'll keep running much too far advanced, and it doesn't seem to be hurting anything.

 

[FORDF250HDXLT]

yeah if someone wants to go outside the book specs thats all cool with me.
thing is,after getting my meter,all that was posted was the high advanced numbers posted by others in the forums.i went by it,and my truck just about had a fit.
if i left it there some serious damage could have occurred for sure (it was much more than standard diesel rattle.)
so im just posting the actual book specs for others.for those who know better,they can go from there.but i feel the actual book specs should be passed on first,followed by "but iv had better results using ...." instead.
this way the next guy doesn't get a surprise when he goes to time his truck using 2-3 degrees and she just about flies apart.

 

[Diesel JD]

Well that is one set of book specs...I've seen others. Your point is valid though, obviously my numbers are not in sync with yours for some reason and you probably did the right thing to back off the timing. You seem to know mechanical stuff and I know running a tree service business you would now bad, scary sounds from normal diesel clatter. Are we using the same luminosity meters (shouldn't matter) same offset etc? (still shouldn't matter) I don't understand what can explain the disparity. Good results are good results though.

 

[Simp5782]

My 85 with 4.10s gets 21/22 empty at 60mph with a 4spd. Loaded grossing 17k - 35k 3 or 4x a day 140 miles round trip I was getting around 9/10 depending on the wind.

My 94 with 3.55s and a zf5 has seen almost 26 at 60/65mph on a trip across south dakota empty.

 

[stevedrums]

My 85 with 4.10s gets 21/22 empty at 60mph with a 4spd. Loaded grossing 17k - 35k 3 or 4x a day 140 miles round trip I was getting around 9/10 depending on the wind.

My 94 with 3.55s and a zf5 has seen almost 26 at 60/65mph on a trip across south dakota empty.

total weight of truck and trailer was 35,000 lbs? holy f***

 

[Brianedwardss]

^ 26 MPG's is quite a claim. I've bested at 23 mpg's once with my 87. It'll get 22 mpg's pretty consistently on long empty trips on the hwy with a light foot.

The only IDI I've ever gotten atleast 26 MPG's with was an '82 Chevy 1500 6.2L with 3.07 gears.