i am looking for new, smaller jets for my mc2100. i currently have 47f's and these are too big. i have tried everywhere around here including the ford dealerships with no luck. i don't think that soldering and redrilling are options for me. if anyone has an idea where i can find new smaller jets i would truly appreciate it.

I am in market for the same thing and have had no luck. There is an other option, Drilling and retaping the carb to use holly jets. However I will not be tring this anytime soon as I need the jeep 6 days a week for work.

Good luck and if you find anything please let us know.

bandhmo

An old timer technique is to solder it up with silver solder then drill it out. The carb mfgr would cringe at this suggestion as I remember reading that drilled jets don't flow the same as they are not properly chamfered, etc and that you ought to buy jets. But on the other hand, if they are not available, what can you do? Try to find some spare jets to work with. Probably have to go to a machine shop supplier to get the fine increments of drill required. Can't see it being that critical the way it's drilled, as you are simply after results.

BTW, I am running 47's in my 1.08 MC2100 on my 258 and have decent looking plugs. I just changed the head as I suspect some oil was coming down the valve guides. I will take another reading in a week or so and see what the new plugs look like. A chassis dyno and co monitor would be great, but that's not realistic where I live. And what would we do with the results anyhow? If jets are not available. I'll have to see what holley jets look like and do a comparo with some MC jets to see what it would take to adapt.

Tim

84 CJ7, 258, HEI, M/C 2100 carb, 5 inch lift, RS9000's, 33x12.5 BFG M/T's, Lockright, full cage & belts, Xenon flares, AMC 20 1pc axles, GM dual diaphragm brake booster

i was mistakenly sent what i think are some holley jets in place of the mc's. they look like they have a smaller thread size so i am confused by those who say that you can drill and tap the carb for holley jets. the holes would just be too big.
i'm going to put in a new power valve and then see if that clears up the too rich condition.

I recently bought an 83 mustang with the 3.8L v6. I haven't looked closely, but it has what appears to be the mc2100 carb on it. Has anyone looked at this carb either as a swap option or a source for jets? I would assume that it runs smaller jets that the version found on the AMC 304, which is the most swapped. Brendan

Proud owner of the world's best running Carter BBD

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Proud owner of the world's best running Carter BBD

Save yourself a lot of time and agivation and don't use one from a ford v6. I tried it and well, it didnt' work. I got a junkyard carb put a kit in it swaped it on and it did run but it ran so lean that I had to back the mixture screws out 8 turns for it to idle. Thoses v6 carbs are listed as mc2100s so I fiquered it should have worked. Well two more junkyard carbs and two more kits latter I fiquered out they dont work. I even changed the jets from 46 to 56 and it ran leaner, I almost had to back the screws out completely for it to run. I finally gave up and ordered a rebiult one for a 304, ran like a beauty. I still havent figuered out why they ran so bad. The lowest jet size I found in one of those was 45, it was of an ltd.

88 YJ: TR upgrade and MC2100

Probably the venturis are too small, so they don't draw enough fuel from the idle passages. I wonder about maybe running the 45 jets in the 304 version? Didn't someone say the smallest they could find were 47's? That's assuming they fit of course. If you guys solve this problem, post your solution or mail me. I'm going to put a 2100 on my new 258 when it's done.

Another thing that I was wondering about, I'm going to be running the 4.0 head on my new 258. would the increased airflow of this head result in a different jet requirement than a stock engine? brendan

Proud owner of the world's best running Carter BBD

You can find Autolite and Motorcraft jets here:
Mike's Carburetor Parts