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Only shade tree kits or swapped in a pre renix setup from the 80s

The modern amc fuel injection system on 4.0 is 1991 and newer

Before that a renix fuel injection system and before that carbs

But first TJ was 1997 so no carbs
 

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I wouldn't step into that nightmare. I am wondering if it is an old motor out of an early YJ.
 

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Or an early XJ

Your first issue is how well it runs especially on a steep incline

Next is no guidance on repairs or repair parts

Next is that it will never pass any emissions tests

Next is substantially reduced resale value

But if ok with all above then you pays your money and takes your chances
 

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Don't touch that Jeep with a carburetor. I grew up with carbs and have tuned/rebuilt them in my younger years and I wouldn't wish carburetors on anyone but someone I didn't like. Except as an interesting museum piece, carbs have no benefit over fuel injection and too many negative drawbacks to list.

One serious problem is how carbs don't work well on steep climbs or descents due to its fuel bowl and float. Think of a toilet tank and float and how well it'd work if you tipped it to the front or rear. Carb'd engines like to stall in those situations. Not to mention they're always wanting you to tinker with them. Carbs are a PITA.
 

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2000 Jeep Wrangler Sahara 4.0L 5spd Money pit Green
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OP might not know a TB from a carb.
Have a look yourself or have the OP send a pic.
 

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Don't touch that Jeep with a carburetor. I grew up with carbs and have tuned/rebuilt them in my younger years and I wouldn't wish carburetors on anyone but someone I didn't like. Except as an interesting museum piece, carbs have no benefit over fuel injection and too many negative drawbacks to list.

One serious problem is how carbs don't work well on steep climbs or descents due to its fuel bowl and float. Think of a toilet tank and float and how well it'd work if you tipped it to the front or rear. Carb'd engines like to stall in those situations. Not to mention they're always wanting you to tinker with them. Carbs are a PITA.
I converted a 97'2.5 auto to a 1960 YF938SD carb, duraspark ignition, mid 70's voyage regulator, and more. Now, as long as I use non-ethanol gas, after eliminating the fuel mileage robbing ECM & fuel injection, I have fuel mileage & more power! I couldn't get over 19mpg on non-ethanol, or 15 mpg on ethanol regular, but now I get 32-34mpg, and can go on the freeway in the wind, now. Stay away from carburetors...my behind!!!
 

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I converted a 97'2.5 auto to a 1960 YF938SD carb, duraspark ignition, mid 70's voyage regulator, and more. Now, as long as I use non-ethanol gas, after eliminating the fuel mileage robbing ECM & fuel injection, I have fuel mileage & more power! I couldn't get over 19mpg on non-ethanol, or 15 mpg on ethanol regular, but now I get 32-34mpg, and can go on the freeway in the wind, now. Stay away from carburetors...my behind!!!
Welcome to the Forum, from Cave Creek AZ.
 

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Los Angeles
1993 Wrangler YJ 4.0
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I converted a 97'2.5 auto to a 1960 YF938SD carb, duraspark ignition, mid 70's voyage regulator, and more. Now, as long as I use non-ethanol gas, after eliminating the fuel mileage robbing ECM & fuel injection, I have fuel mileage & more power! I couldn't get over 19mpg on non-ethanol, or 15 mpg on ethanol regular, but now I get 32-34mpg, and can go on the freeway in the wind, now. Stay away from carburetors...my behind!!!
Welcome.

As long as you remain on a freeway, you can have your carb. Ascending a trail with irregular angles will drain your fuel bowl, and then what? You have to back down and hopefully find somewhere flatter to get your bowl filled up and a lot of times you need to prime it.
I used to have to get a running start at a hill so i could get up and over before my 2150 sputtered out, even though my 400ci had enough torque.
So glad i wised up and left all that nonsense.
 

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Lol...understood! I only did this conversion 7 weeks ago. I was ticked off the ECM went out completely. A few years ago, the charging side of the ECM went out...I worked around that. This time I decided I had enough of no fuel mileage. I drive 17.5 miles from the house, to the farm, and I like my jeep, it's too handy. I tried to get an ECM, quickly, and without having to trailer it to a dealer to program it, so I picked up a new distributor for an 84' CJ, a ignition module from my 78' LTD Landau, the carb from my 60' Willy CJ5, pulled the fuel robbing junk off the intake. Use the base gasket as a template. Drilled and tapped for the carb. Put in studs. Put the carb on, put a choke cable on. Added a 2-4 psi fuel pump inline. Added a switch for that. A switch for the original pump, to be a pre-prime for the other one. Made a quick wiring harness. Had it done in a weekend and fired it up. I then had to add a switch for the torque converter lockup. It would lockup at a stop, unless I downshifted to 2nd, now no issue. I had to set the plugs to .032", and play with the timing. I haven't thought about hills, but I get about 33mpg, and run it around most of the day, stopping, and going, and bouncing around. No issues yet. When it was good before, it'd slow down, in the wind, not now. It's very peppy! I can't complain. Now, I tried ethanol, and I have to open the mixture 1.25 turns, and adjust timing 3 degrees then it seems to have half the power, won't idle very well, and can only get about 11 mpg. Just gutless on ethanol gas. So, my thought is, I'm glad the ecu went out, and I did this. For me, this is great!
 

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Los Angeles
1993 Wrangler YJ 4.0
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^^^^My hats off to you and the story is riveting but I don't buy it for a second, lol. I do not believe that you are going to mix n match together a carb kit that is more efficient than a stock fuel injection setup.

And you are including pictures for posterity?

Sidenote: I just bought a used ecm today because they are getting tough to get. Maybe I need to buy a Street Demon carb too...
 

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FYI: you mentioned 400CID, and 2bbl. In both my 78' LTD, 79' F250 have 400 Cleveland's in them. I put aluminum 4bbl intakes, and an Edelbrock on the truck, and a Holley on the car. The F250 has a Dana 61 w/3.07:1 gears and gets about 17- 18 mpg, and the Landau has 2.74:1 gears, and get 21.74 mpg, both on Non-ethanol. If I use ethanol, I have to change timing, and mixture, and they both will ping. The car then gets about 12 mpg, and the F250 gets about 5.5 mpg, then. Computers, and ethanol are, in my mind going backwards, for fuel mileage, dependability, and it makes the engines run hotter. The problem is , as expected with the last election, fuel is outrageous, again, but that's the usual pattern, since before we got away from points, or added they cats to our toys. Oh, none of my older vehicles, to include my Keeps, have cats on them. Not needed here.
 

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You don't buy it, eh? What did cars in the 80s get for fuel mileage, with carbs? Think! Oh yeah, there wasn't ethanol ( corn resin), either. Or, look at the old henry J model. 49+ mpg. Plymouth horizon 42 mpg. 77' Town Car w/ 460 mechanical FI...24 mpg. 74'vega 35 mpg. 76' Dodge B200 van 318 2bbl 3 spd manual on column 22 mpg. 83' Mustang GT 4 spd 4 bbl. 3.08:1 gears...23 mpg. 87' F150 351W 4 bbl...21 mpg, but now a 2007 F250 6.2l get 12 mpg if your lucky? 2015 Chevy Impala...20 mpg. Backwards!
 
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