Single to double barrel carb switch on 85 2.5L

[ReverseCurse]

I've got a 85 CJ7 with the 2.5L 4 banger and my little carter/weber YFA carb is on it's last legs. I'm in the process of rebuilding it but I keep encountering other problems with it as I work through. I want to make the switch a double barrel, I want to know what I need to buy to make it a viable switch. From what I've seen, the double barrel carbs that are on the inline 6 have a different mounting plate to the intake. I was wondering where I could find one to fit my intake... Can anyone help? If any of you have any of this laying around, I'll buy it right up!!

 

[mriplaybass]

First of all, welcome to the forum!
I would check places like Summit, JEGS, etc. Before you do this, make sure you are not going with too much carb for your engine. The old F heads don't really need a lot of CFMs to run great. This was discussed recently on this forum for other engines, and there is a formula to roughly calculate how large of a carb you need based on the displacement of your engine. http://www.jeep-cj.com/forums/f2/2100-motorcraft-carb-series-cfm-ratings-25865/
check out PeanutButter's post which is #2 in this thread.

 

[jzak]

I went though a similar issue with upgrading from a 2bbl to a 4bbl on my previous CJ. I thought it was just about switching out my Carb, but you'll probably have to put in a new intake manifold, and depending on the engine it may not make any difference in performance. Some engines just cant take advantage of the extra airflow.

 

[ReverseCurse]

So I reckon I ought to just find another single barrel carb... Any recommendations on a possible upgrade?

 

[Lumpy Grits]

:ww:


Why not just rebuild what you have now?
What is the engine do'n, that makes you feel that it's a carb issue?
Good place for parts and such.....
http://www.jwjeep.com/

LG

 

[ReverseCurse]

Well the carb is leaking fuel out of the little butterfly control on the front, the whole rod going into the carb there is loose inside and its just leaking gas out.

 

[Hedgehog]

Rebuild it with a linkage bushing job. Sometimes it's not about the amount of air you can stuff in your engine, it's about the velocity of the air flowing through the carb. Remember, your CJ wasn't designed to be a screaming high RPM beast, it's designed to grunt just off idle when you need to bump over something like a rock or small tree or get the manure wagon moving. That is here air velocity over the jets is king.

 

[CJim7]

I ran a Weber 2bbl on my old 2.5 and it ran awesome with the addition of an RV cam. As far as a stock engine, I would research the performance level of such a carb on this engine before making the leap.

You don't need to change the manifold, but you will need the adapter. Weber/Redline sells them.

Sound like the throttle shaft is worn out. Not a lot you can do in that situation as that tends to wear out the journal and leaks forever. (Q-jets are bad for this)

 

[Lumpy Grits]

Rebuild it with a linkage bushing job. Sometimes it's not about the amount of air you can stuff in your engine, it's about the velocity of the air flowing through the carb. Remember, your CJ wasn't designed to be a screaming high RPM beast, it's designed to grunt just off idle when you need to bump over something like a rock or small tree or get the manure wagon moving. That is here air velocity over the jets is king.

lg