2.5 Carb upgrade

[TheIronSausage]

Hi all,

 

     First, I'll come clean and say that I've got an '84 XJ, not and MJ.. However, like my '86 Dodge 4x4, it makes more sense to belong to the Ramcharger site than it does the truck site.. You guys and gals are better suited to my needs than the eighty other more modern Jeep sites.  At any rate, having dealt with stoopid computer controlled carbs on my Mopars (Throw over shoulder, do not attempt to find)  is there another carb that will swap onto my bone stock '84 2.5?  For reference, I do have eight other antiques as daily drivers, so I'm not necessarily looking for long and involved modifications like Renix, or TBI.. I need my garage space for maintaining my junk, and doing side work.  There's got to be a relatively simple swap out there.. Carter BBD? (based on cable linkage instead of the BBS rod linkage) Weber DGA/EV?  A 20 OZ bottle with pinholes punched in the bottom?  Something's got to be better than a computer controlled carb.  By the way, I do intend on off roading this thing.  Nothing crazy, It's not getting a big lift and 33" tires, it's plenty capable in stock form except for the poorly metered fuel leak dressed up as a carb atop my engine.  It will be seeing climbs, and rocks, and mudholes, as well as creeks/rivers.  It's a $700 Craigslist Jeep.  I'm going to use it as such. 

 

Thanks in advance!

Matt

[MJanky]

Hi all,

 

First, I'll come clean and say that I've got an '84 XJ, not an MJ

 

 

Asking about a carb sort a gave it away :)

 

I can't tell you yet because I'm still working on other projects before I convert my MJ to a carb (too many projects) but the first thing I'm going to look into when I do is adapting a Carter carb from an old Willys L or F head 4 cylinder. It might already match the intake pattern, I'll probably just order a Willys gasket to check first. The linkage idk but it ain't rocket science. The jetting ought to be about spot on for the 2.5 AMC. One thing is for sure, it doesn't get any simpler than one of those. I'm thinking manual choke and everything.

 

It does look a little tall though so it might need a hole in the hood with a hood scoop or something.

 

I'll know eventually I just don't know when at the moment. It is on my list of things to do.

[TheIronSausage]

 

Hi all,

 

First, I'll come clean and say that I've got an '84 XJ, not an MJ

Asking about a carb sort a gave it away :)

 

 

Huh, that would explain the dearth of info turned up when I searched for carb upgrades here.  I've since found a Weber WK552 conversion, which includes the proper adapter to put a 32/36 DGEV on a 2.5, but I don't have three hundred bills to lay out for it..  I also kinda prefer homebrewed concoctions anyway.  It's more fun that way.  So, I suppose that asking what vacuum controls I can toss out of my engine bay may not yield a bunch of results either?  The Jeep actually seemed to run well before the catalytic converter plugged up when I was climbing a trail with it.  It's got 108,xxx miles on it, and it sat in a field down by a treeline since 2009.  Everything seemed pretty original to it, and the vacuum actually worked the shift fork on the front axle, but I locked the collar mechanically to be sure.  Anyways, since I don't give a hoot about passing emissions tests, I want to unlock this wheezy little bastard's full laughable potential without rebuilding it.  I know that speed parts are nil, but somebody's created something for it..

[MJanky]

Yep I think the only Comanches that ever came with a carb were the 86 models with the optional 2.8 GM V6, the only year they used that engine. The Comanche came along a couple years after the Cherokee and the 2.5's on them were all fuel injected.

 

I'm one of the few around here that even thinks "downgrading" to a carb is a good idea, but there have been others. You aren't likely to get much carb input here.

You might try a YJ forum, more carbed 2.5's there (I think those even still had carbs thru 86) and I'm sure owners have dumped the computer controlled ones. When I carb my MJ, I'm sure as hell not using the stock XJ/YJ carb. But there ought to be plenty that will work. I do believe I've seen write ups for bypassing all the computer stuff on the stock carb if you are so inclined so that might be an option for you. I need a carb so I'm just going to get what I want to start with.

 

I won't advise you one way or the other on if you should do it. Only you can decide if it is the right choice for your needs. I don't know how much having the computer control carb would help for offroading mostly because I don't care but it might so you may want to look into that before ditching it.

[Eagle]

I don't think a carburetor "upgrade" is dumb at all. I have an '88 MH 2.5L and I'm seriously considering getting rid of the throttle body injection and switching over to a carburetor.

[Eagle]

I have a friend in Greece who used to own a 1984 XJ 2.5L. In fact, that's how we met -- through NAXJA. I asked him about his XJ, because I thought I remembered that he had a Weber conversion. I was right. Here's what he just e-mailed me [Note: I think by "double throttle" he means two-barrel]

 

 

Sure I remember it, the carb it came with stopped working a month or two after we got it. I ordered a double throttle Weber and it fit perfectly, and worked like a charm, but I no longer remember which model it was.

 

Of course, all the smog equipment was removed from the car, and it was not registered as an unleaded model here, even though it came with a catalytic converter. But Greece didn’t got any laws about unleaded and catalytic converters until much later, so that was registered as a regular gasoline car. Removed all the stupid things that had to deal with polution, discard the catalyst, installed the Weber and used …. I think I was using regular gasoline, but I ain’t sure anymore.

[MJanky]

The Webers are good carbs if you can afford one or find a deal on a used one. The ones they sell in kits are usually the same carb with slightly different jetting depending on the vehicle and the adapter plate to mate it to the intake. Then they offer a choice of choke- manual, electric or water. The main difference is if you choose the progressive or synchronous 2 barrel. The synchronous one will work on a stock engine but is really for performance out of a hopped up engine. If you plan to stay stock go with the progressive.

 

I do suggest researching the Weber for offroading. I know they work good on the street but I've seen some gripes about them from the wheeling crowd, though many do use them. IIRC, they offer or did offer one set up for offroading but it was even more $

[Marine1Texas]

from what I remember you can use 32/36 DGEV or a 38 DGES both are 2 barrel carbs. 

 

 

Below link shows the kits for webber carbs for 2.5, 2.8, 4.0, and 4.2 Jeep engines. You don't have to get the kit, but the carbs are what I think your looking for 

http://www.redlineweber.com/carb-kits/auto/jeep/

[MJanky]

I think by upgrade the OP means more simple than the computer control carb he has, not necessarily better performance.

 

If looking for better performance then the Weber is the way to go IMO. But if you just want simple an old all mechanical one barrel will work.

[MJanky]

Oh and if you like the Weber you might be able to use a Holley 5200. I don't know if I ever saw someone use one on a Jeep but I've seen them used on other vehicles in place of a Weber. You can get one cheaper so it's sort of a poor man's Weber conversion. You'll still need an intake adapter since it's a 2 barrel.

[Eagle]

One other thought -- My friend in Greece also did some kind of ignition upgrade when he did the Weber carb conversion. I didn't remember what it was called, but it came back to me. Google "Nutter bypass."