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Discussion Starter #1 (Edited)
I have seen many people request and want to see what everyone is getting for fuel economy. Somewhat similar to the dyno thread, I want to start a thread with just an individual fuel log.

Just create a post and include some basic information

Date Odometer Reading Miles driven Gallons MPG

Please include a description of your conversion.....

Please just post if you are posting a fuel log.

IHRAcer...
I would only post the last 20 or so entry's. If you have more than that you could also include what your overall stats.
 

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Discussion Starter #2 (Edited)
Fiddleback Fuel Log

1979 Ford F-150. 4BTA, VE pump, 3200 spring, no fan, straight 3" exhaust, t-18, NP205, 3.73 gears and 35" tires. I drive it like I did with the 351M. No baby'n and no abusin.

My odometer is off. So, I mutiply my OD numbers by 1.088 to get my actuals. Number shown are from my Excel Spreadsheet
Actual
Date----------Odometer-----Miles Driven----Gallons--- Price---- MPG-----Notes
09/27/2008_______96715___________0_________________________________First Fill up
10/11/2008_______97040__________353________17.7____3.499____19.96
10/20/2008_______97333__________319________15.9____3.559____20.05
10/26/2008_______97851__________270________14.2____3.219____18.95
11/08/2008_______97821__________261________14.1____2.899____18.47
12/12/2008_______98080__________282________15.6____2.459____18.1
01/10/2009_______98393__________340________16.8____2.129____20.3
01/30/2009_______98664__________295________15.3____2.199____19.2
03/12/2009_______98914__________272________14.0____1.959____19.4
03/26/2009_______99215__________328________16.9____2.099____19.4
04/11/2009_______99512__________323________16.8____2.119____19.3
04/26/2009_______99708__________213________11.3____1.999____19.0
04/30/2009_______99948__________261________12.9____1.999____20.2
05/20/2009______100238__________316________16.2____1.979____19.5
05/23/2009______100364__________137________10.0____2.199____13.7____Filled up nose down
05/23/2009______100687__________351________12.3____2.159____28.6____I think underfilled
05/31/2009______100756___________75_________8.2____2.069_____9.4____See above
06/12/2009______101015__________282________13.0____2.349____21.6
07/10/2009______101310__________321________16.4____2.459____19.6
07/18/2009______101587__________301________17.8____2.499____16.9
08/03/2009______101928__________371________18.7____2.439____19.9
08/15/2009______102280__________383________19.1____2.559____20.0


Average mpg--19.32
Total savings vs gas (7mpg) is $1,137 or average of $54 per fillup and 552 gallons of gas

I figured that I need to save $5000 to be even, so I'm 22.74% to my goal.

More to come....
 

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Sorry I dont have the actual numbers in front of me but I have checked the mileage over the course of 3 tanks of fuel.

I am averaging just over 32mpgs with about 60-65% city and the rest on the highway. I average 45mph around town and 65-70mph on the highway. My conversion is the truck in my sig with a weight of 3860#.
 

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How many entries do you want? I have a spreadsheet with every bit of fuel consumed by my truck since June of 2007. My current overall average for the 19,918 miles driven and recorded is 18.30 mpg. This includes extensive towing miles, and 4 months (approx 3,500 miles) of driving on two bad injectors where my BEST mileage was 16.88 mpg in that period. The average from April of 2008 to present since I installed my new POD injectors (7,726 miles) is 19.47 mpg.
 

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I'm averaging about 23, city and hwy combined. Still in the works, however, and I think I can improve that...

Engine hasn't had the "screws turned to it".

Intercooler in the works, along with SAS. Getting ready to reseal the IP.


4BT 92 F150 4x4, straight exhaust, 3.54 gears w/32" tires...

:beer:
 

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69 EFB, manual trans no OD, 3200 spring 28 mpg hiway(against gov. 90% time)
 

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Mix of hwy, city, towing, wheeling all pushing 38s with 4.11 gears using a medium to heavy right foot gets me an average of 18mpg. I believe I can get better once I solve a few issues. My goal is for mid 20s.
 

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I found a old .xls that I used way back starting in 2000. Here are the specifics:
1992 Dodge CTD(6BTA) 5sp 4:10 gears 35/12.50x16 BFG MT, 4" exhaust, stock fueling.
Trailer towing was for a 25' Airstream
Gross combined weight was just under 13,000 lbs.
Towing speed was limited to 65 mph.

The findings for the year 2000:
For 14,387 miles I used 945.03 gallons, 498 engine hours at a cost of $1,419.58
Average mpg was 15.224
Average gallon per hr was 1.897
Cost of fuel per mile was $0.099 per mile

Heres the all the data in the .doc
 

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1994 Dakota Ext Cab Short Box 4x4. 120HP VE 4BTA, 47RH. In town mileage is about 23-24mpg. Highway mileage is 28-29mpg. Towing 5500lbs mileage is 13-14mpg. Fuel screws have been tweaked, and 3200 gov spring installed. Stock injectors and stock turbo. Empty the pyro reads 800 degrees at 120kph/70mph, and about 4lbs boost, rpm is 2000. No specs for towing, didn't have the gauges hooked up in time.
 

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You guys should list whether your vehicles are auto or manual and what RPM's you average on the highway. Probably makes a large difference ;)
 

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85 Chevy 2500 4X4 4sp with 372 gears the 4bt. I checked it on three tanks and got a little over 23 mpg. That is on dirt roads, turn row driving and with about half of the miles on the highway. Got a 98 Dodge 3500 4X4 5sp with 355 gears that gets 13+ doing the same thing. Just cant get in a hurry, it will only run a little over 60. I dont have a tac so dont know how fast it is turning. It has the 235-85-16 tires.
 

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1994 Jeep Wrangler

Area of Operation:
United States, South Eastern Indiana

Current Configuration:
Engine: Cummins 4BT Stock Turbo
Transmission: General Motors TH-400 3-Speed Auto
Transfer Case: New Process 231
Rear Unit: Ford 8.8 (2.73)
Front unit: Jeep Dana 44 (2.73)
Tires: Mickey Thompson Baja Claw (33x15.5x15)

Fuel Record:

2007
P. Date - Odometer - Qty - Price - MPG
10/20/07 - 000,000 - 17.00 - 0.NA - 19.5
11/15/07 - 000,331 - 10.00 - 3.50 - 17.2
11/19/07 - 000,503 - 05.70 - 3.50 - 16.3
11/20/07 - 000,596 - 14.29 - 3.50 - 18.2
11/26/07 - 000,856 - 18.30 - 3.54 - 18.1
12/12/07 - 001,187 - 19.70 - 3.30 - 15.0
12/24/07 - 001,483 - 18.10 - 3.33 - 16.4
Annual MPG - 17.24

2008
P. Date - Odometer - Qty - Price - MPG
01/16/08 - 001,779 - 18.52 - 3.35 - 16.4
01/29/08 - 002,083 - 19.10 - 3.30 - 14.2
02/20/08 - 002,355 - 16.77 - 3.58 - 17.8
03/05/08 - 002,653 - 07.90 - 3.78 - 20.2
03/21/08 - 002,813 - 19.50 - 4.16 - 14.8
04/03/08 - 003,101 - 19.47 - 4.06 - 16.0
05/24/08 - 003,690 - 18.90 - 4.83 - 18.6
06/25/08 - 004,041 - 19.35 - 4.86 - 19.3
07/07/08 - 004,414 - 19.55 - 4.86 - 18.6
07/28/08 - 004,778 - 20.22 - 4.70 - 19.5
08/20/08 - 005,172 - 19.55 - 4.59 - 18.8
09/17/08 - 005,547 - 19.96 - 4.16 - 17.7
Estimate - 005,925 - 20.50 - 4.05 - 18.6
11/01/08 - 006,307 - 19.75 - 3.09 - 17.6
11/25/08 - 006,655 - 20.80 - 2.69 - 14.9​
Annual MPG = 17.53

2009
P. Date - Odometer - Qty - Price - MPG
Estimate - 006,965 - 20.50 - 2.16 - 15.0
02/24/09 - 007,272 - 19.46 - 2.16 - 17.8
03/16/09 - 007,619 - 20.01 - 2.00 - 17.2
03/24/09 - 007,963 - 19.19 - 2.19 - 17.7
04/06/09 - 008,303 - 20.00 - 2.20 - 18.5
04/19/09 - 008,672 - 20.01 - 2.26 - 17.2
05/22/09 - 009,017 - 19.33 - 2.33 - 17.1
06/22/09 - 009,347 - 20.75 - 2.70 - 17.2
07/12/09 - 009,703 - 20.31 - 2.66 - 17.4
08/16/09 - 010,057 - 20.01 - 2.70 - 17.9
09/09/09 - 010,416 - 20.01 - 2.70 - 18.0
09/30/09 - 010,776 - 20.92 - 2.60 - Soon
Annual MPG = 17.36

Overall MPG: 17.38
 

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9944 miles AVG:19.4mpg to date 88 k5 blazer, 4.5" lift, 33 BFG M/T's, 3.42 gears, 3200 spring, 4l80e trans low stall converter
I'm becoming more and more skeptical of the 30mpg+ guys, I hope to find the secret one day
 

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My 97 TJ Jeep since May 24, 2010 to Oct 18, 2010 is averaging 16.7 mpg 100% city driving. I am using the AX-15 5 speed with 4.10 gears and 35" tires. My mods on the engine are 50 hp injectors from Scott, turbo is the H1C with the 12 cm3 exhaust housing and a 58mm compressor wheel water aftercooler and the power screws turned way up....
 

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After driving and tweaking things for over a year and a half I was getting mid 16's and 17's for mixed driving mostly city with short distance trips. On longer trips keeping my speed below 65mph I was able to get 21.5mpg as my all time best for all highway. This was with 37" irok radials.

I recently made the jump to FHODYS and mileage is down so far by a few tests I have done. I have gotten similar mpg's in city driving but on 2 seperate tests I was only able to get 16.5mpg and 18.2mpg on all highway driving. Strangely enough I got the worst mileage when I drove 65-70mph and better when I tried keeping it at a little above 70mph. Head winds could be a factor in this.

I have also taken into account and compensated for the odometer/speedometer reading differently with the taller tires.

The reduced rev was what I was aiming for with the larger tires, but the increase in unsprung weight of about 43+lbs x 4 makes the engine work a lot harder. I saw an increase in my egts of about 100-150* with the new tires.

I just removed the "fuel sock" which is the in tank fuel filter and it is running alot better. Next I am going to try advancing the timing a bit more and see what happens.

Most likely I will do the M&H ksb timing spacer and report back.
 

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2008 jeep wrangler rubicon
4bt 140 hp
nv4500
4.10 gears
33 inch tires


last tank was 29.02 mixed town /highway-454 miles on 15.6 gallons
previous tank was 24.9 mixed driving
previous tank was 22 mixed driving.

new engine is breaking in great
 

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I've got a 1990 4BT installed in a 2006 TJ Unlimited. She's got an AX-15, 35" BFG KOs and 3.07 gears.

If I keep her at 55mph in 4th gear ... I can regularly get 29mpg.
If I keep her at 70mph in 5th gear ... I can regularly get 22mpg.

It takes forever getting anywhere at 55mph, but with a 31 gallon GenRight fuel tank, getting 900 miles on a tank of diesel is pretty awesome.
 

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Mine mpg has changed since I built it . and I don't know why. My motor was used with 89K on it when I got it. Mine is in a 72 Bronco with NP435 and 3;55's and 285 /16's . I use mine on the farm and at 1st I was staying in low range & driving the farm in 3 gear .. and I was playing in the crossing the creek at several different places just for fun. Now after it's been running for over 2 years now I'm in high range and 1st & 2nd gear. AT 1st I was getting about 12 an 13 .. BUT THE LAST 2 tanks I got 27.4 & 26.2 much better.
 
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