4.0 with 2.9 electronics?

[kunar]

okay before you even start reading.... dont give me crap for thinking outside the box. ive got a simple question and i want some real answers

now my question... would it be possible to use a 2.9 distributor on a 4.0, along with all of the 2.9 wiring and sensors? now i know that the easy way to do the swap is to use the proper 2nd gen ranger 4.0 wiring and it will all swap. but i was figuring that if the distributor from a 2.9 fits in place of the oil drive on the 4.0, thats the hardest part out of the way. the other main concern is fooling the computer into getting the proper a/f ratio. im not exactly sure how to accomplish this...

the reasoning behind all this is because i have a freshly rebuilt 4.0, and a ranger with an old dying 2.9. and im missing some of the electronics for the 4.0

 

[Wicked_Sludge]

i know there is A dizzy that works in the 4.0...as ive seen them converted to carb. before. im not sure if its the 2.9 dizzy thats used.

the injectors are too small. you can replace them, but then the computer wont be properly metering the a/f ratio (like you said). im sure the spark and fuel curves are different between the engines, so even if you get it running, it wont develop the power it should. tuning EEC-IV is a PITA, but it can be done. maybe whats-his-face at bamachips could burn you a custom chip with 4.0 fuel and timing curves for the 2.9 PCM...

if your trying to save yourself the "work" of swapping the 4.0 wiring harness over, you arent suceeding with this route.

 

[Ozwynn]

yeah the 2.9 PCM is tabled all wrong, how you get a dizzy to work on a 4.0L.

on a gen 2 a 4.0L swap is almost plug and play.


edit: but it looks like you got a gen1

 

[rickcdewitt]

still plug and play if he grabs the dash too.totally though,why lose a ton of power?and spend more than the cost of whatever he needs for a 4.0 setup?

 

[turbo cat]

If you want to really get into it you can look into a Megasquirt ecu to tune the fuel and what not but theres alot to lean and work to do in that case. I would just hunt down a parts truck people wreck gen1s all the time and seel for only hundred(s)

 

[Psychopete]

the other main concern is fooling the computer into getting the proper a/f ratio. im not exactly sure how to accomplish this...

You might not ever get it right. I'd be curious if it would run on a 2.9L MAF computer, if a TFI 2.9L dissy can/could fit. With an IST Air Adjuster, I was able to "fool" the computer enough to run 19lbs injectors, a reground cam, and other mods.. It still won't be right, but I suspect that it might actually run.

Pete

 

[turbo cat]

Megasquirt has an adapter board to adapt mega to the EEC IV ford ecu. Then you could tune the setup with a wideband 02 www.DIYautotune.com

 

[kunar]

a MS setup had crossed my mind but im sure not gonna be saving any money. i had figured on using bigger injectors to try to fool the computer. when i get my engine back, i will be checking to see if a 2.9 distributor will fit in place of the oil drive and cover that fit there. but still, if i could find a 2nd gen ranger with a 4.0, i would be all set... i know you can swap in the explorer dash too but i dont want to. i like my boxy 1st gen.

btw, i do have the 4.0 computer to use... im sure it wouldnt do me any good if i was using a distributor though. i dont have any of the 4.0 air box or duct work though, and i dont have anything that would have been mounted on the truck. i do have the engine wiring harness, the coil and all of the accessories though.

 

[turbo cat]

The ecu woulnt work the pin outs will be different it probally woulnt run at all even thou the ecu will plug in. If you fool the ecu you might be ok and then you might not. I would just go to the junkyard and pull a full wiring harness that woudl be the best cheapest way. Also the distributor isnt goin gto clear the intake.If you waste your time trying to fool it and it dosent work youll probally just be wasting time

 

[MAKG]

First rule of control systems -- garbage in, garbage out.

You WILL NOT fool the computer and get it to work sensibly.

 

[Sevensecondsuv]

You could probably use a distributor with the 4.0L DIS computer. For Ford TFI (like the 2.9 has) and DIS (like the 4.0 has) the computers have all the same ignition outputs (IDM, SPOUT, PIP). The only difference is that on a 2.9 you've got a TFI module controlling a distributor and with a 4.0L you've got a DIS module controlling a coil pack. The computer doesn't care what it's sending the IDM, SPOUT, and PIP outputs to, and the input signals IDM, SPOUT, and PIP are the same for a TFI module or a DIS module.

This swap has been numerous times by 2.3 turbo people, myself being one of them. I'm currently running a TFI computer (from an 88 turbocoupe) with a DIS ignition from a 90 ranger. Works great.

The 4.0 DIS is supposed to run at 10 degress BTDC with with SPOUT connected disconnected. So just unplug the SPOUT connector, twist the dizzy to 10 degrees BTDC, plug the SPOUT connector back in, and the 4.0L computer won't ever know the difference.

*All this is based on my experience with 2.3 setups. It should apply to all Ford computer/ignitions, but I guess it could be difference for the 4.0L.

 

[almostclueless]

First rule of control systems -- garbage in, garbage out.

You MOST LIKELY WILL NOT fool the computer and get it to work sensibly.

Fixed.

Being the rather intelligent person you are, you should know to never say never....

 

[Wicked_Sludge]

For Ford TFI (like the 2.9 has) and DIS (like the 4.0 has) the computers have all the same ignition outputs (IDM, SPOUT, PIP).

well if that were the case, couldnt he just use the 2.9 computer to control the 4.0 DIS? this saves him the "trouble" of swaping the 4.0 electronics in, and the real trouble of finding a dizzy that'll fit/work.

 

[turbo cat]

swappin gthe 4.0 electronics in isnt that big of a deal. Just buy a wrecked first gen ranger/explorer with a 4.0 they can be ahd for only hundreds and then you will have everything adn a truck to go off of when you start the swap. you can possible fool the 2.9s ecu but dont be suprised when you get no where and the truck woulnt run right

 

[kunar]

im trying to avoid spending a bunch of money. i dont have the time or the place to be able to get a donor vehicle. if anything i would have to find the truck at a yard and pull the parts. i dont want to cut and splice a bunch of wiring which im sure i could do if i had to, but i dont want to put that much time into it. i havent decided on anything yet, i just had an idea and threw it out there. ill have to spend some time looking through my evtm's and see what i can find.