Hi there. i'm new to this forum. I have a 06 Rubicon, but it is my weekend toy. I bought a 1986 Comanche about a year ago. I rushed into it, against my sometimes better judgement.Any way, my problem is that the engine won't run or idle after about two weeks, I clean the plugs, and it will run ok for about another two week or so, then foul out. It has a Webber carb on it, and will not lean out. I use it every day to go to work. I was wondering about a cheap swap, and what it would entale. I have the 2.8 V6, 4wd and automatic. If I tried to swap a 4.0 in, will the rest of my drive train be able to stay ( bell housing, transmission, transfer case), and how hard would it be to to wire up the the engine compartment. I have heard that a 3.4L V6 from GM will bolt up, but haven't been able to find any info. Does anyone have any information I can download to guide me thru this? Thanks for any help.