3.9 to 5.9 magnum swap in my 2000 Dodge Dakota

[olds307 and 403]

It revs smooth and it has serious torque like it should. Yes, it was very frustrating.

 

[Texas82GP]

Well after the truck just running shitty after the head swap, I found 2 issues. First it was running on 7 cylinders, number 8 had a wire off on the injector. Noticable miss, I guees so. Second is the reason the truck has run shitty on and off. I "upgraded" to a brass BWD cap, some upgrade. It never sat on the motor properly, wouldn't tighten down, pretty sure it was moving, causing shitty running. It got really bad barely running, I had a Champion cap, brand new. I found the rotor with the spring broken off. This cap tightened down all the way and replaced the rotor. No more bad missing or violent shaking in reverse. Finally!

I sold auto parts in the early 90's. BWD was good stuff back then. No more. I gave up on them close to 10 years ago. It's a shame.

 

[olds307 and 403]

I agree, BWD used to be quality stuff, most products I have had good luck. I couldn't get any brass contact caps locally except the BWD and basically it was old stock. The Champion is aluminum like AC Delco but at least it tightens down properly. I am pretty sure this cap was the reason for the on and off poor running.

 

[Texas82GP]

I agree, BWD used to be quality stuff, most products I have had good luck. I couldn't get any brass contact caps locally except the BWD and basically it was old stock. The Champion is aluminum like AC Delco but at least it tightens down properly. I am pretty sure this cap was the reason for the on and off poor running.

Really glad you found it. I had read in a few threads how frustrated you were and felt your pain. I think many of us have been there. I know I have.

 

[olds307 and 403]

Yah, this easy swap has been anything but easy. I sent the ECM back twice still not right but I worked around it, jumped #7 and #8 injector. The trans has also been a POS, codes and limp mode even after changing the sensors. I added toggle switches for OD and lock up. I just jump power at the relay connection and have all the gears, 5500 rpm shift points. I just throw the relay in around town so the battery doesn't drain. Also the command start is not right, attempts to start and flashes four times, there is a guy that does them all the time, 2 streets over.

 

[olds307 and 403]

It had a little miss but other than that, ran great on a 3 hour return trip. I am going to check the cap and rotor again, plugs and put back on my MSD Superconductor wires I took off in desperation, currently a mismatched set. Either way, no over heating and good power. I am going to figure out mileage today.

 

[olds307 and 403]

I figured out 14.25 imperial mpg, not great but seem to be inline with what most 5.9 magnums get. It was also nearly -30 Celsius, drops the mileage considerably, should be able to pull high teens in warm weather. Our Challenger drops 10 mpg from Summer to the coldest part of Winter but I doubt if I will gain that much.