Carb Swap Question

orngjp

New member
70 CJ5 258

Swapped in a Motorcraft 2100 carb last week.... runs great. Only problem was the carb was off a 1971 Ford Truck and didn't have a port for PVC. For now i am using the vacuum port that i think was originally used to provide heat to the choke coil to assist in heating it up??? Not sure of this, but it is a tube that has full vacuum at idle and lead into chamber near the choke coil.... seems to work for now.

Anyone know if this is going to be a problem or have any other ideas??

Thanks for any thoughts.
 

I have a YJ with a 258 and the Carter carb and want to do a swap for the 2100 as well. I've heard great stories about the swap and am glad to hear another positive comment about it! Good luck finding your answer, you'll get a lot of good advice in here!
 
Have you heard of a HOLLEY #8007 390 CFM 4-BBL. CARBURETOR conversion kit? It comes with the intake manifold and a 4bbl carb that is supposed to replace the Carter BBD. I have been thinking about making the leap, but am hesitant. Know anyone who has made the conversion from 2bbl to 4bbl? What are the pitfalls?
 
don't know anyone personally who has made the conversion to the holley 4, but i would think that would work best on an engine that has been modified to increase hp.
motorcraft swap has been great so far.... better idle and definitely a big improvement off road on inclines.
 

Anyone do the Moorcraft or Holley swap for a Carter where they have to smog the vehicle?
 
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I just today swapped my BBd for a MotoCraft 2150. What an improvement! I got the carb off an '80s F150 for thirty bucks. I got the proper rebuild kit from the first parts house I passed for $15. An adapter (from Mr. Gasket PN 1937) cost $15. A blind monkey could rebuild one of these things and various jets are available from... everybody. I'll need to putter with the fuel/air trim to get it tuned for emmisions testing, but what the hell, for 60 bucks I have a CJ that actually is a gas to drive. Just make sure you select a carb that has a PCV spot and ports for all that other stuff.
One surprise; The electric choke from the Carter apparently turns opposite from the choke on the MC, so I'll need to find one with the coil going the other way, or I wonder if the coil could be flipped....?
My advice; Don't be intimidated, chuck that Carter POS and bolt on something (anything) else.
 
Have you heard of a HOLLEY #8007 390 CFM 4-BBL. CARBURETOR conversion kit? It comes with the intake manifold and a 4bbl carb that is supposed to replace the Carter BBD. I have been thinking about making the leap, but am hesitant. Know anyone who has made the conversion from 2bbl to 4bbl? What are the pitfalls?

A friend of mine ran a 4bbl on his CJ for a few years. I don't know what CFM his was. His has a cam, headers, and dual exhaust. He is going to install the 2100 in it's place. Even with his mods, it is too much carb for the motor. I just put the 2100 on mine. I don't know about fuel mileage yet, but starting, power, and throttle response are much better than the Weber I had on it.
 

I did the MC 2100 swap on my '84 CJ and I highly recommend it.
I hope this helps;
The adapter is available from Mr. Gasket. The part number is 1937.
Jets are easily available and all the jet part numbers start with 120-4-??
If you look at your jet and it says 46 on it, the part number would be 120-4-46 and the orifice size would be .046"
If, with these jets, your carb seems to be running rich, you could order a pair of 120-4-44 and try that for a while. (Reduce the size at least two sizes or you may not even be aware of a change.) The cost of a pair of jets is about 7 bucks.
A Neihoff kit for the 2100 should be about $15 but it dosn't come with jets. It does come with a power valve and unless you taking this 2100 off something radical, like a BB Ford or somethig, it should work okay.
Once you bracket the proper size jets and the best power valve, share the intel my brother.
For parts go to;
http://www.swapsupply.biz/
This guy has it ALL!
 
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