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Discussion Starter · #1 ·
I am currently rounding up the peices for my hei swap, in addition while searching out parts,I have come across an Offenhauser 4BBl manifold for my 258, most of the learned jeepers out their consider a motoraft carb the optimum setup .can anybody offer any opinions of what the best size FOMOCO carb is to fit and what might be a good vehicle and years to pick from. thanks all.

Tommybear
86 CJ RUNNING 295'S WITH A 258&T5
96 RAM ecab running 295's also

 
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Discussion Starter · #2 ·
I friend of mine is using this very same setup, Offy 4 bl intake on a 258 with a MotorCraft 2150 2 barrel, and GM HEI. His little 258 really kicks a** with the power output. He used the 2150 from a AMC 304. It was a great swap and great for the off-camber trails.

Peanut


 
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Discussion Starter · #3 ·
the cheapest motorcrafts are early seventies fords with v8s. most are about 350cfm to 500 depending on year and cu in displacement of the engine. the earlier models do not have smog crap on them either.

dan

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the 2150 is a 2100 carb with an idel compensation solenoid ont he back, they are interchangeable carbs...

its a pretty good low CFM carb, not quite the performance of a 2300 Holley 2BBL, but a decent carb...

I have one for sale by the way...



ozarkjeep
1977 CJ5 looking for a Hard top near NW Arkansas!
 

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I forgot!!!

sources for autolite 2100-2150s..

small block ford trucks, ford mustangIIs...full size JEEPS with AMC V8 2bbl have this carb...including Grand Wags built into 1991....



ozarkjeep
1977 CJ5 looking for a Hard top near NW Arkansas!
 
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Discussion Starter · #6 ·
If you can't find one at a junk yard, last year I bought a rebuilt motorcraft carb for my 304 for $115 at O'Reillys Auot Parts. Carb was rebuilt by Holley, but its still the motorcraft design.

 
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Discussion Starter · #7 ·
The question you raise, Tommy bear is one of interest to me. You seem to have settled on a 2bbl as opposed to a 4bbl. However, you are obviously wanting more power and performance, I assume, - so why not choose a 4bbl. I thought that the 4bbl could give better gas mileage if ones foot was not on the floor and also performance when ones foot does go to the floor - compared to the 2bbl. So what are the advantages you see of using the 2bbl over the 4bbl and what are the strengths of the Moto as compared to either the Holley, Rochester, etc.? Appreciate your thinking on this.

Mindbender
CJ7 258
 
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Discussion Starter · #8 ·
the advantage of a moto over most other carbs is that it will almost run upside down with little or no mods. most four bbl carbs have too much fuel in their bowls and are prone to flooding. motorcrafts also have next to no parts in them so there is little to go wrong(except accellerator pumps, always carry a spare). and they are cheap.

dan

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Discussion Starter · #10 ·
not without a loss of flow. there are adaptors made to do this, but i recommend an intake swap. the stock intake is too restrictive, especially at the carb base.

dan

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Discussion Starter · #11 ·
Are you saying that only the Motocraft 2bbl will run upside down and that the Motocraft 4bbl, because of the increased bowl size will not work as well on climbs, etc.? Or, is it that the Motocraft 2bbl and 4bbl both share this ability to almost run upside down. You also indicate "with little or no modifications"? What modifications if any might you propose?

Mindbender
CJ7 258
 
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Discussion Starter · #13 ·
the moto 2100 works fine on a stock 258, but put a offy or clifford intake with it. this way you will recieve maximun benefit from the work.

moto 4bbl carbs are junk. and i am a ford fan from day one. they never could get the secondary system to be reliable. and as far as running upside down, the more fuel in the carb, the easier to flood.

mods are simple, rebuild it with a good kit including a brass float. chase all passages with a stainless wire to ensure good flow. you can set the float a touch low (max 1/8in) but i think running and adjustable regulator works just as good without the worry of starvation on the highway.

these are not performance carbs, but they do work well for mild power applications. here in the NW they are referred to as "po mans injection".
you do want to carry a spare accelerator pump for them as they are prone to dying when you least expect it.

dan

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Discussion Starter · #14 ·
This is a little off base but how do you compair the moto to a weber??????
Price wise would be close. By the time you buy the 4 barrel intake.

 
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Discussion Starter · #15 ·
webers are good carbs. but they do require a little studying up on to make the best of them. they offer a lot of things most carbs dont, but if you do not know how to take advantage, the carb might leave you feeling like it is not right.

i still think that you need to replace the stock manifold. without taking a die grinder to it, its never going to really deliver for you. just remember that an engine is an air pump, the more effectively you deliver and expel the air, the more power that can be produced.

dan

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