You said you are alreasy having issues with the engine idling and dieing.

Address those issues first. You may find that fixing what is already wrong with it may lead you towards your goal of more power. The 2.8 wasn't a hercules of motor to start with and if yours has problems now, you are just sapping what power it did have.

Check ALL the vacuum lines to make sure they are not cracked or missing and attached correctly. Many times that was a major issue with these engines. There are other cost effective upgrades for this V-6 out there. Once you get it to running correctly.

 

I haven't changed out the plugs and wires yet. I just got back from a trip to Texas so I'm a bit low on cash at the moment but as soon as I can get my hands on some green I'll change those out.

As for the vacuum lines, I've changed a few but I'll go out and look at them closer today.

And yes, I'm a girl that LOVES to get her hands dirty! They haven't developed the constant black tint yet (like my boyfriends) but I have a feeling I'll be close when I get done with this rig. I have big planes for it but I can't rightly go on with them until this whole engine thing is worked out.

 

I almost forgot...

There were two versions of the 2.8l

An early version with the weak crank journals that GM dumped onto Jeep.

And the later version that had the problems worked out of it and was used in a BUNCH of GM stuff. This version also had TBI injection in later years, which was numerous times better than the carb. It was a self-enclosed set-up. You can get a TBI intake,TBI unit and its related computer and install in place of the carb you know have.

 

hmm I'll check into that, Thanks a lot

 

This, I did not know.

I owned an '85 Jeep Waggie with the "bad" 2.8L, and an '88 Chevy Eurosport with evidently a "good" 2.8L. Is it possible that cherokeebaby has a "good" 2.8L, or that she could just do a 1 for 1 swap for a later model year "good" 2.8L???

 

That she has the better version? No. GM only sold the early version to AMC.

That she could do a 1 for 1 swap? Yes.. but it needs to be a RWD motor. The castings are in the wrong places on a FWD motor.

 

Anyone have a link for installing a 4.0 out of a 87in place of the 85 2.8 so far i see the radiator mount is diff.and how does the firewall wiring harness come apart?looks like a retaining clip on engine side around the junction block

 

Big project. The early v-6 models need to have the firewall cut to fit the longer motor. The header panel won't work either.

Much easier to swap in a 3.4L GM V6. It's a direct swap for your 2.8l

http://www.3400swap.com/

 

heres my situation the trans is bad in the 2.8 rig.White..fender off I have a good 4.0 with 5spd. if u look in my pics u can see the donor gold one..looks like a fun project

 

Junk the 85 and get ya another old beater witha 4.0. You can usually get them pretty cheap.

 

If you want to keep the Jeep then swap in a 3.4L V6 and get the tranny rebuilt. Otherwize you need to find another XJ with a 4.0L engine.