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Old 11-21-2003, 01:00 PM
midnytrambler midnytrambler is offline
Join Date: Nov 23, 2002
Location: Hartford, Wisconsin
Posts: 85

Has anybody seen any mileage increases from the TFI or HEI ignition conversions? How about the Howell or Holley fuel injection kits? I'm sure either will improve drivability and starting, but will they return anything in gas savings, or power? I'd like to hear some first hand testimonies on these, so I can justify spending the cash on my '89 Grand.
Old 11-21-2003, 03:38 PM
AMC258 AMC258 is offline
Bleedin' Gasoline
Join Date: Apr 07, 2003
Location: Oroville California
Posts: 2,456

Swap in a 258
Aaron McGuin <br /><br />80 Cherokee (The Short Bus) <br />Rebuilt 258<br />T176/NP208<br />31x10.50x15 OTR Muds from High Tec Retreading<br />84 GW (Gabby)<br />258/TF999/NP229<br />really bald 235 75R15s<br />Slowly becoming a shell of its former self.
Old 11-21-2003, 04:35 PM
mtn goat mtn goat is offline
Bleedin' Gasoline
Join Date: Apr 30, 2001
Location: Boise, Id, USA
Posts: 1,729

midnytrambler, Further along the cost/benifit analysis how much you really get if one were to pay for for fuel injection.

lets see, lets say you can get a projection unit installed for $1200 bucks, and lets say that gets you 3 mpg better(going from say 12 to 15). Now how many miles would you have to drive to get the cost back. well, if you get 3mpg better and gas costs an average of $1.60, you go from paying 13 cents a mile to 10 cents a mile. Thats a savings of a grand total of 3 cents a that into the cost of the projection unit...You should pay for the fuel injection in only 40,000 miles.

SO, is that worth it? You decide:P [img]tongue.gif[/img] [img]tongue.gif[/img]
\'82 Cherokee WIDE TRACK<br />258/T176/NP208/D44/20 Rack of Tad, BIG Orange fender, funny blue hood!<br />I must go and tend to my molecules, they need me to grow big and strong...Polymer Power!!!!
Old 11-21-2003, 04:59 PM
SBJeep's Avatar
SBJeep SBJeep is offline
Master Mechanic
Join Date: Aug 14, 2003
Location: Santa Barbara, CA
Posts: 926

Drive slow. I usually get 12-12.5 on the highway at 70-75. This summer I lost a wheel weight and had to go only 60 or the Jeep would shake violently. To and from Vegas I got 14.5. I'm back down to 12 since I don't have the patience. Maybe you do.
Tom - '90 GW(Gone)
Old 11-22-2003, 09:58 AM
Mondo Bat. Mondo Bat. is offline
Master Mechanic
Join Date: Feb 12, 2003
Location: Eugene, Oregon
Posts: 802

Take off the body and weld you seat to the frame rail...
wear goggles.


Put an overdrive tranny in.


but in a 258 with a weber carb and a T5 tranny, I get 22-25 MPG with that.
Seriously, gravely, not off topically yours- Patrick the Jokeless Lemming.
-SOLD- Pretty 82 WT CherokeeSearching for another WT; Got one?
Old 11-22-2003, 02:44 PM
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badaboom badaboom is offline
AMC 4 OH! 1
Join Date: Jun 05, 2001
Location: High Country Colorado, USA
Posts: 3,753

Try little tikes at "toys are US".
They have Jeeps.
Runs electrically from battery.
Very affordable.
Weight capacity Poor.

It just goes to show AH its allows something.
1981 Jeep J10 Laredo, 401-V8, 625 Carter, Lunati 262/268, Edelbrock Performer, MSD Ign., Hydroboost, Hyd. Clutch, Flow Cooler WP, Be Cool Aluminum Radiator, Doug Thorley, NV4500 5-Spd, NP-231D, 3.73 F/R Trac-Locs, Rustys 4" Lift, Vintage Red Metallic, Black Interior and 33X10.50X15 BFG, FiTech400 to come - IN PROCESS Bling Bling Cha-Ching
Old 11-23-2003, 01:41 PM
TexasJ10's Avatar
TexasJ10 TexasJ10 is offline
360 AMC
Join Date: Jan 03, 2002
Location: Houston, Texas
Posts: 2,774

I don't think fuel injection should be written off so quick as a less than worthwhile project. Afterall, you can get a very good kit from for $800 and there are other benefits besides fuel economy. EFI engines tend to last longer since they are not dumping unburnt fuel into the cylinders like carburaters do, and they don't react to inclines like carbs do. I think the cost can be easily justified especially if you have a newly rebuilt engine.
* 1981 stepside, 360, 727, 208, almost stock daily driver.
* 1982 Laredo j-10, 360, 727, in rough shape and in the process of being rebuilt with 401, NV4500, Klune,
. NP205,d60 front, d70 rear, fender work and minimal lift. It will probably take 10 years
* 1973 jcab mounted on 1983 j20 frame. 360/t18/208 d44/d60. Almost completed
Old 12-01-2003, 10:30 AM
Erick Erick is offline
New Member
Join Date: Nov 15, 2003
Location: Knoxvegas
Posts: 17

Dont accelerate too fast, and avoid braking and stopping when possible. Also with all the weight of FSJs, they can coast for a very long time after a long downhill. Use this momentum to your advantage. This strategy helps me to get the most out of my last quarter-tank of gas.
1979 camaro sbc 350 4-bolt mains, 10:1 compression, hp 400<br />and best friends 1982 Wagoneer 36\" TSL and 4.56 gears.
Old 12-01-2003, 06:01 PM
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Don S Don S is offline
Gone,But not Forgotten.
Join Date: Feb 06, 2002
Location: Burleson TX
Posts: 5,613

Erick.. Good ideas! I wrote down a bunch the other day.
... The engine converts gasoline to heat as the power source. Fifty percent of the heat is wasted unused and is dissipated though the radiator and exhaust system. Large cubic displacement engines consume more fuel than smaller engines but this is not a ‘hard’ fact.

... Here is a list of a few mechanical things that can effect fuel mileage. Cam and ignition timing, cam lift, duration and valve size. Fuel delivery systems, and exhaust scavenging systems. Operating temperatures of fuel and engine. Type of transmission, gear ratios, type of tires, tire size, the tire pressures and the wheel alignment. The vehicle speed, the load, the wind speed and direction. The list can continue on including the gasoline and of course the driver.

Is it possible that larger wider tires require less ‘toe in’ that could reduce drag?

The driver knowledge and ability is the big factor for achieving the best fuel mileage if the vehicle is in proper condition. Make sure the odometer in the vehicle is showing correct mileage. Keep a record of all fuel amounts, the mileage and the Miles Per Gallon between each gas-up. The record can be helpful in spotting problems with the engine when there is a sudden drop in mileage. Full tank amounts will vary due to air trapped in the tank but the MPG will average out in the long run.

Here are a few thoughts about saving fuel.

First thing a driver will notice when they start to conserve fuel is it will agitate other drivers around his vehicle. Please be considerate of other drivers who have no concept of your economy driving. The other drivers want to race to the next stoplight and remember, if they don’t get there quick enough they won’t get to stop!

1. Think about driving as an art while doing so. Stop rubber-necking, turn off the music, the cell, and drive.

2. Install a dash-mounted vacuum gauge and use it. As the fuel mileage drops the vacuum needle drops. Try to prevent the needle from dropping below five inches. Readings will change with altitude changes.

3. Drive as if you had a fresh egg taped on the accelerator AND brake pedals.

4. Apply accelerator and brake pedals smoothly.

5. Reduce speed as much and as soon as possible. Speeds above 50 MPH eat into the pocketbook!

6. Scan far ahead of your vehicle for traffic control signals and things that will allow you to ‘get off the gas’ sooner so you don’t have to ‘hit’ the brakes as hard – later. The over use of brakes means fuel has been wasted.

7. Drive as if your afraid your brakes are in poor condition and you are trying to save them.

8. Purchase your fuel in the morning when it’s cool and keep the tank full.

9. Air you tires up when they are cold and on the plus side of the recommended pressure and check them often especially on cold days.

10. Small amounts of high quality low ash Out Board 2 cycle oil in the fuel (less than ¼ Oz per gallon) will clean and lubricate and reduce friction in the following items for better fuel mileage and life, electric gyrator fuel pumps, carburetor/injector parts, spark plugs, valve stems, compression rings and EGR systems.

11. Air dams can enhance cooling and reduce aerodynamic drag. Bug shields, sun visors, wind deflectors and large outside mirrors can reduce fuel mileage.

12. The effect of heavy loads is detrimental to fuel mileage and brake life.

13. Modifying a vehicle with lifts and large wide tires is detrimental to fuel mileage and brake life.

14. Cruise control may save fuel in ‘flatlands’ but may not be economical in hilly country.

15. In hilly country do not allow the down hill run to cause engine ‘braking’ i.e. slowing down the vehicle unnecessarily. Run your fastest speed at the bottom of a hill and the slowest at the top. If you are on long steep grades it is very difficult to stop while going down hill. On these long grades use engine ‘braking’ and even down shift for added speed control and to save the brakes.

16. Allow the engine to warm up and/or drive gently till it does. Cold engines get poor fuel mileage.

17. Put the transmission in neutral or stop the engine when long waits in traffic are encountered i.e. train crossings.

18. Reduce the Air Conditioning and the electrical demands on the alternator. Fancy lights and sound systems burn extra gasoline and bother others eyes and ears.

19. Hey!.. wake-up!! do you have any other ideas?

I posted this mess at;

Have a good one and CUL.. Don S..
Sold our 1976 Wagoneer 406, MC4300, TH400, QT, TruTrac, 2" lift, 31x10.50s, duel Optimas,
It’s took us over 161 Colorado Mountain Passes, 3 Jeep Jamboree USAs & 2 Ouray Invasions from 1985 to 2010
Old 12-04-2003, 04:36 PM
loborph loborph is offline
Join Date: Mar 09, 2003
Location: Albuquerque
Posts: 76

I was getting 16mpg after I put on my Jacob's ignition and leaned the carb out. But then I lifted it and put on the 33's - now its down to a predictable 12-13mpg .
82 Wagoneer, 3\" Rough Country, RS9000/9700, 3.31\'s w/ 33x12.5, oba, Jacob\'s Ign, rear lockright

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