4.0 distributor swap

[nesralyrrej]

Hey guys, been a while since my last post, have my a ranger with tired 2.9 into it and I want to put a 4.0 into it, but I don't want to go into all the trouble of swapping all of the harnesses, so I figure I could swap the dizzy from the 2.9 to the 4.0 and keep my harness the same, any ideas? Is it possible? Maybe put the 2.9 intake on the 4.0 heads? Any help would be great guys, I've had it with this gutless motor

 

[adsm08]

Um, what "trouble" swapping harnesses? On your 90 if you get a harness from a 90-92 4.0 Ranger it will plug right in and work, and most guys I know pull the harness with the engine because it's just easier.

I think it will ultimately make more work, because a speed/density probably won't deal well with having 1.1L of displacement added if you try to use a 2.9 computer, and the 4.0 computer will probably be confused looking for stuff that is now missing. Unless you find a MAF 2.9 computer, which are pretty rare.

 

[RonD]

^^^ +1

2.9l used distributor(TFI) and MAP(speed density system) sensor

4.0l used the MUCH more reliable EDIS(distributorless) and MAF(Mass air flow) sensor system.


Speed density system computer can't adjust to higher air flow of larger engine, so you would run lean.
And how many times have you had to work on the TFI system?

Either rebuild the 2.9l or get 4.0l with wiring and computer

 

[nesralyrrej]

I've been looking for a 90-92 4.0 ranger in every junk yard for 100 miles and have yet to find even one, that's most of the trouble,

and I've read a few forums where people swap the under dash wiring and the body harnes' just to put the 4.0 in their trucks, but I've read some where they say that's you don't need to do any of that,

I have a quarter horse eec-Iv tuner and figured I could tune it to make up for it..

I have also been looking into harder swaps just because I can source the parts much easier, I looked at an ecoboost v6 but I can't find a manual tranny for it that's even close to reasonable so that got scrapped,

I've been looking a lot into a pushrod 5.0 or 5.8 I even have a built 390 with no home I could squeeze into it a lot but the m/t and t/c seem almost as hard to find for those as well as getting everything to work properly