Hey everyone I have some questions about my swap, I have a 1990 dakota LE with a 3.9 magnum efi I blew up my transmission and wanted to make a project out of it.
I got a 5.9 gasser out of 2000 ram 1500 I got the engine the wiring harness and the pcm. After looking further into the swap I was told I might be better off staying with getting a 94-97 first gen 8v harness and pcm from there it's basically plug and play to some extent. Any info pointing me in the right direction is appreciated this is my first engine swap

 

The 3.9 is basically a cut down 318 engine. The 5.9 is a 360 engine. The 360 is balanced differently than the 318 and 340 engines along with the 3.9. Did you get the transmission from the 2000 with the engine? Keep in mind, your 1990 isn't a Magnum. There are a few differences between Magnum and non-Magnum engines. They are close and it should physically fit, but I think the motor mounts are a little different and so on.

 

I did not get the transmission out of the 2000 but i did get the external balanced flywheel so I think I'm good on that front?. From what I've seen also the fitment shouldn't be the problem even if the mounts need a little adjustment.

 

Yeah, you really want the earlier electronics, 93 to 95 if you go OBDI (and an RH trans) or 96-97 if you want the RE trans. 98 and up just won't work, too much changed in how things ran.

 

if I were to stay in the 93 to 95 years for OBD1 if i get a harness from a 318 engine and the pcm will the same pcm work for the 5.9? Or do I have to modify the harness or pcm further

 

Harness will be the same between 5.2 and 5.9. It's essentially the same engine... A 5.2 PCM will run the engine lean in open loop, which isn't a real good plan.... but, so far as I know, the computers were the same between the full size trucks, and the Daks, so, an OBDI computer from a full size truck that had the 5.9 should work just as well.

 

You blew up your transmission, so you bought a an engine with all of the wiring and ECM. You don’t say what transmission that you are putting into the project. Are you running auto or manual trans? Is the donor of the 5.9 an auto or manual?
the the 5.2 and 5.9 have the same harness and mounting positions, not sure about the 3.9.
the OBD1 has no “tuning” capabilities, unless you upgrade on board logic chips. The OBD2 is the way to go in my opinion. At least it has flashing/mapping adjustment capabilities when you have a chassis tune performed,
if you are planning on changing from auto to manual or vise versa, you’ll be creating even more issues.
would love to offer more advice, but need to know all of the particulars.

 

I did not get the transmission out of the 2001 ram only the engine ,engine harness and the pcm. planning on staying with a auto trans not sure what one yet hoping i can use the one out of the parts dakota i just got its a 92 318.not exactly sure what trans is in either that or my 90 v6 ill figure that out today. i was hoping to stay obd1 if i could. if i were to go to obd2 I would not be able to use my stock gauges and cluster concert? that's why I'm hesitant of switching if i can keep my hands out of the cab of the truck that would be great for me.

 

since my last posts i came across a 92 5.2 at my local shop guy bought it for the headliner an back bench, the rest is all still there, engine doesn't run suspected fuel issue, pcm and harness look to be intact. would this 92 v8 harness work for my 2001 5.9? also been looking for obd1 5.9 pcms with no luck, can i re flash the 92 pcm or soemthing like that? i have the 92 in my yard right now to take some other parts for my truck but engine wise is there anything i should take off that is combatable with the 5.9? ill have it until the landlords complain haha so might have it to long before I scrap it.

 

What year is the trans in your truck?