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Discussion Starter · #1 ·
Have a few K based 84 Lebarons that I have been working on lately.

Between the 2, I've been able to sort one out and determine that the LM in the 2nd one has a Bad AIS circuit.

Both LM's look like they have been replaced and also look the same, silver painted but no labels.

My first thought for long term dependability is;

What is the newest straight swap in E/C harness and ECU that I could upgrade these to?

The K based models went to 89ish? Is there a chance the dash-back wiring remained the same through most of those years?

At the very least, I would think that 84-86/87 would have remained the same and could swap the e/C harness and LM directly in?

Anyone with any info or experience in having done this would be Great to hear from you.

On the flip side, now that most of it is sorted out, I could just replace the 84 turbo LM in the 2nd Lebaron and see how things go.

When I search, I see a lot of these out there, from Rockauto to ebay. Can anyone with 84 Turbo LM recommend one from another?

Also, how many 84 Turbo LM's are there? Rockauto only lists 1, but doing some research I've found that most say there are at least 2, Some believe there are many depending on vehicle (like later years) while others say they are indeed, all the same.

Can anyone confirm?
 

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The sdac ecu listing shows only one 84 lm 4798477 for mt & at. Mopar performance lm for 84 is 4529868 or old# 4349139.
Id think swapping to an 85 lm would be easiest, just have to figure out boost control. 86- up Lm you would need to change to the bigger distributor also. Hopefully somebody with more knowledge will chime in as well.
 

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1984 was all by itself, and there were two different power modules. The boost control was purely mechanical. 1985-87 there are several LMs, but one PM for all turbo applications. When I was building my 1985 turbo Lebaron, I was told that the 1987 Daytona electronics were the best ones to use. The LM could be socketed and brought up to the 4 wire AIS the T2 used.

As for there being only 2 listed, probably correct, if it is like others I have dealt with, early production and field use uncovers problems, this requires different programming of the "brain" so a new updated LM would be introduced. Reman units are usually the latest version produced and supersede the earlier versions.
 

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Discussion Starter · #5 ·
1984 was all by itself, and there were two different power modules. The boost control was purely mechanical. 1985-87 there are several LMs, but one PM for all turbo applications. When I was building my 1985 turbo Lebaron, I was told that the 1987 Daytona electronics were the best ones to use. The LM could be socketed and brought up to the 4 wire AIS the T2 used.

As for there being only 2 listed, probably correct, if it is like others I have dealt with, early production and field use uncovers problems, this requires different programming of the "brain" so a new updated LM would be introduced. Reman units are usually the latest version produced and supersede the earlier versions.
So what did you end up doing on your 85?

I remember doing a mittsu Caravan years ago, believe it was an 84 as well. IMS we swapped in a 2.2 turbo using a turbo harness from wrecking yard. May have been 84 to 84 though.

I'm going to see what manuals I have and check the pin outs over the years to check compatibility.

Was hoping someone else had already figured this out, and surprised if someone hasn't.

Maybe NAJ can chime in with bulkhead pinouts for K based cars 84-87 if I don't have the manuals or can't find the info.
 

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Discussion Starter · #6 ·
I may have an extra 84 lm if you'd like me to check, i've tried it in mine before i started converting the harness over so it does work, shoot me a dm if you'd want it.
Thanks for the offer. My debate over A/M new vs old original rages on as time goes by and the thought of original eproms loosing their memory becomes an issue.

Can't say I've seen this be an issue so far, but they say there is a life to them and then poof, gonzo!
 

· Old School Hot Rodder
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On my 1985 Lebaron, I used the 1987 Daytona LM socketed so the tune could be changed easily. PM was the standard 1985-1987 turbo one, 5226766. The harness needs a wire from pins 16 and 20 on the red connector to run the 4 wire AIS stepper motor.
 
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swapping adifferent engine compartment harnessisgonna be an extrapain
the 84 hada40 way bulkhead connector like L bodies

and every bit ofwiring back is likely 84specific
I tryed 84 power doorwiring to an 86 daytona
lol
totally different at thevdoor jambswhere it plugsto thedash harness ..and so on
the 84'sarethelast ofwhat I'll refer to s "the volare / aspen era"
ie sameconnectors ..thingsstart changing in 85..I think first yearfoe50 way and the connectors start being used
by 86 it'sall the 87-9 style connectors

the84'srear body wiring should bethesame though ..fuel pump tail lamps but the connector at thedoor jamb are likely different


sorry my space bar/keyboard is kerbluie
 

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swapping adifferent engine compartment harnessisgonna be an extrapain
the 84 hada40 way bulkhead connector like L bodies

and every bit ofwiring back is likely 84specific
I tryed 84 power doorwiring to an 86 daytona
lol
totally different at thevdoor jambswhere it plugsto thedash harness ..and so on
the 84'sarethelast ofwhat I'll refer to s "the volare / aspen era"
ie sameconnectors ..thingsstart changing in 85..I think first yearfoe50 way and the connectors start being used
by 86 it'sall the 87-9 style connectors

the84'srear body wiring should bethesame though ..fuel pump tail lamps but the connector at thedoor jamb are likely different


sorry my space bar/keyboard is kerbluie
If looking to upgrade the engine harness only, there is no need to touch anything from the interior bulkhead back with exception of adding a couple of wires; one for the fuel pump and one for the power limited light, both of which are at a white connector by where the logic module would use to sit. I should make a write up after I'm done with my conversion for 84 specific since the only one i have found was from 20 years ago with broken attachments (thanks way back machine) lol How-To convert 84-87 T1 to 88+ SMEC T2 . Pretty much keep the wires for your lighting up front and change everything else over from the new harness. Makes it easier to have another engine side bulkhead connector so you don't have to take every wire out of the original bulkhead connector, keep it intact. Pretty simple once you get into it. Started mine up last night with the new smec module and it fired right up. Will need the smec harness, all newer sensors and newer distributor/hep, and alternator.
 

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If you're not planning to tune, I'd just fix the LM and go on. Not worth the effort to swap a harness and other potential unknowns that come from used parts. If wanting to tune, then 87 LM swap for sure. Just my 2 cents. I haven't done the swap but have considered it. I'd love to find a clean 84 convert and swap to 87 electronics along with decent turbo and probably a 5spd.
 

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Discussion Starter · #11 ·
Just a quick update; Ordered LM from Rockauto and it was wrong. Did not match photo on website and was solid case, no blocked off MAP location and no round grommet plug on case like the 84 factory LM's I've seen.

Contacting Rockauto to try and sort this out as this should be the simplest LM to order, should really only be 1!
 

· Old School Hot Rodder
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swapping adifferent engine compartment harnessisgonna be an extrapain
the 84 hada40 way bulkhead connector like L bodies

and every bit ofwiring back is likely 84specific
I tryed 84 power doorwiring to an 86 daytona
lol
totally different at thevdoor jambswhere it plugsto thedash harness ..and so on
the 84'sarethelast ofwhat I'll refer to s "the volare / aspen era"
ie sameconnectors ..thingsstart changing in 85..I think first yearfoe50 way and the connectors start being used
by 86 it'sall the 87-9 style connectors

the84'srear body wiring should bethesame though ..fuel pump tail lamps but the connector at thedoor jamb are likely different


sorry my space bar/keyboard is kerbluie
FWIW, 1985 Ks still had the 40 way bulkhead connector, and all the wiring went down the left side underhood, then crossed under the radiator in the support lower channel to the right side. Only thing that helped me was the 1985 had the feedback carb on the Mitsubishi 2.6 so when I converted to a 2.2L T2 the large firewall hole on the right side was there.
 

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Discussion Starter · #14 ·
Funny, as I look further into this, not sure what I believe.

I've heard that there was only One LM for both auto and Manual for turbo 2.2's in 84.

I've also read that there were 2, but one of those 2 was just an upgraded unit, like a 1/2 year flash upgrade.

To date I've prob found at least 6-8 different part numbers and I believe at least 4 of them. Have seen listings for both auto and manual and different listings for different cars.

So what's the deal, does anyone actually Know what's what with the 84's?
 
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