I was wondering if anyone has swapped anything like maybe a Weber carb or something that performs better onto there carved 3.9 to get rid of the problematic feedback carb and so I can maybe get a bit better performance out of the v6. Not looking for much just a little extra. Dont want to swap to a v8 the v6 does pretty good on fuel really for what I use it for.

 

Well, you'll also have to figure something out for the ignition, since the feedback controller ALSO does all spark advance, and they never had a vacuum/centrifugal advance distributor for the 3.9.

Being uneven fire, you have to fiddle with a 225 Slant Six dizzy; and being a UNIQUE uneven fire, you will have some running problems with, say, a Buick V6 dizzy.

To upgrade, I'd recommend going for a TBI base unit, or upgrading to a Magnum.

RwP

 

Mopar used to make an ignition kit, or you could buy just the distributor, that would give you electronic ignition. It had both the vacuum and mechanical advance..... But has not been sold in lots of years. The feedback was going bad on mine and would cause it to stumble when accelerating. I just cut one of the wires going to it..... FWIW I considered a 2bbl off of a older 318, also considered one of the chinese knock off carbs. like this. https://www.ebay.com/itm/Brand-New-C...frcectupt=true But have decided to eventually convert to a carbed 5.9....


FWIW I believe the ignition would continue to work as is, without the factory carb, so I think you could switch it.

As ralph was saying some have claimed to have used an even fire distributor..... I think it takes the SBM V8 distributor, but the reluctor wheel and cap from a slant 6.... But I am sceptical..... An even fire will hit on 120 degree rotation. The v6 in our trucks is, "I think" 112 and 128 degrees.... It may run, but I dont believe it will run right!!!

 

Summit sells the ignition kit to swap to electronic ignition. I'm using it on my Magnum swap in a 91 ram. From Mopar performance. Not sure about the v6 though.

 

What are you using for vacuum and centrifugal advance?

That's the problem; spark isn't, advance timing IS.

RwP

 

It's a duel setup. Vacuum and mechanical. I'm not using the vacuum advance. I'm not really after mpg on this build. It's got the performance curve advance, also adjustable. Pro-form makes it, but it's Mopar endorsed. Comes with everything. Wire harness, orange ignition box, distributor, cap, rotor, ballast resistor. I run allot of wot so the vacuum advance won't work anyways.

https://www.summitracing.com/parts/pro-440-426?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-proform-parts&gclid=CjwKCAjwvuzkBRAhEiwA9E3FUtJDa9o_WkxJg5 FXmkfhpphIfb_nUybuDELPlfVcWbYPG-PW5YvNshoC00MQAvD_BwE

It's for the v8s though. I haven't looked for v6 setup. Might be able to change the reluctor in the dizzy to a 6. I believe they are pressed on. Don't mind the 440-426 it's there part number for the small block setup, lol.

 

Yes, that kit, which is made by pro form and then licensed under Mopar, basically took the place of the orig. performance electronic ignition conversion that Mopar made. Problem is, its for a small block mopar....
Nothing is made for the 3.9 V6 motor.

At one time Mopar offered the performance distributor, 4bbl intakes, cams, etc for the 3.9 but again, this was all discontinued several years ago.

 

Yeah, the 3.9 doesn't have anything going for it anymore. I had a 3.9 in a 03 Dakota got the same gas mileage as a V8. I averaged 15 City or highway. I actually get better mileage out of my 2500 with the 5.7. both are straight drive 5spd. I can get 17 with this beast. Both 4x4. If I ran 5th gear in my Dakota I averaged 14. So I never ran 5th only going downhill lol.