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Discussion Starter #1
I have a question about this items.Are they bound to what ever car they come out of ? Like say i have a N/A car with a auto transmission can i swap out the transmission to a manual and use the logic module & power modules that are in the car or do you need to swap them out too ?Are the turbo logic module & power modules the same as the N/A ?
 

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The short answer is that it really depends on the year and which engine management system your car has installed in it. The 84 year turbo cars are unique, only an 84 turbo logic module or turbo power modules will work in an 84 turbo car, NOTHING else will work. The NA cars use a different engine management system. The power modules LOOK the same, but there is at least 1 wire not present in a NA PM that is present in a turbo PM. The LMs also LOOK the same, but the electronics and programming inside are totally different. None of the NA engine management pieces (except maybe for some sensors) can be used on turbo cars, or vice-a-versa.

85-87 turbo cars all use exactly the same power module, and the TI logic module is pretty much the same between automatic and manual tranny cars, but there are some difference in the idle control programming. The L-body logic module for 85-87 cars is different than non-l body cars, the big difference is that all L-body LMs have an integrated MAP sensor. There was a change in the MAP sensor on 87+ cars, but not for the L-body. Non l-body car LMs are basically the same but some of the pins are in different places than the L-body cars, the engine fuel/timing tables are different (g head vs fast burn head), and a difference in AIS motors between 85-86 and the 87 style (4 wire) for the most part the logic modules non-interchangeable. So for example, all the 85 logic modules for turbo cars are pretty much interchangeable (except for slight differences in idle control manual vs automatic) with other 85 cars. The same is true of 86 turbo cars, they are interchangeable with other 86 cars. And in 87, the TII logic modules are interchangeable with other TII cars from 87 as are the TI cars except for the L-body cars which as I pointed out earlier, ue an integrated MAP sensors where all other cars have an under hood MAP sensor..

There are of course exceptions, and the inclusion or not of cruise control is also a factor, some LMs have, some don't.
 

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Discussion Starter #3
Ok im understanding it now so could i make a N/A car with a auto transmission a manual and use the logic module & power modules that came with the car ?
 

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The answer would be yes, there is a difference in the reverse light switch for the automatic vs manual and you might also have to deal with the neutral safety switch...

Most the forum members would probably agree that the interchangeability and compatibility differences in the programming between a manual logic module and automatic logic module would be negligible. I think that the only and most significant difference has to do with idle control when in 'Park' vs at idle and when coming to a stop. I know for sure that there are members that have played musical LMs on their cars w/o any driveability issues that they even noticed or that made the car unpleasant to drive. So the tribal knowledge is generally it doesn't make a whole lot of difference. Opinions may vary and so may your mileage on this can of worms topic.

Of course it's always best to have the correct LM for the car and tranny you actually have.
 

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Did Chrysler switch to a two wire neutral safety switch? On all my old cars I just ground the single wire to the chassis to make the solenoid, or depending on the year, relay operate.
 

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Discussion Starter #6
ok i get what your saying.I can make it work but its best to just have the right one or ones.I just have to find the logic module & power modules for a N/A stick shift from a 86.
 

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Did Chrysler switch to a two wire neutral safety switch? On all my old cars I just ground the single wire to the chassis to make the solenoid, or depending on the year, relay operate.
Manual transmission cars only use a two wire reverse light switch. Auto cars have three wires. The third being a neutral safety wire going to the ECU. If that isn't grounded, the car won't even try to start. But if you just ground it when switching from an auto to manual, you lose cruise control(if you care about that). So I ran that third wire back into the interior and mounted a small switch on the clutch pedal so when I depress the clutch, it grounds the wire and allows it to start. When you release the clutch pedal, it breaks the circuit, and allows the cruise to work.
 

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Discussion Starter #10
I dont care if cruise control works i just want a N/A car with a manual transmission instead of a auto transmission.I looked on Ebay on logic module & power modules and most of them don`t say if its from a auto or a manual.There was afew that did but most don`t.
 

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with the auto electronics you might have a slightly fast idle with a manual as the auto would be programed to maintain some pressure in the auto trans that would usually slow down the auto trans equiped motor due to load while idleing
 

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Discussion Starter #12
So i technically use the ones from the auto and make it manual but my idle would be alittle higher and i would have to ground the third wire on the neutral safety wire for it to even start .
 

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So i technically use the ones from the auto and make it manual but my idle would be alittle higher and i would have to ground the third wire on the neutral safety wire for it to even start .

Basically, yes.

I've been running the auto SMEC in my Daytona for almost two years now. Only issue I've noticed is that on deceleration, when I press the clutch in the rpm's will drop to about 500-600 for a split second, then it will catch & return to the normal 900 rpm. Other than that, it runs fine. I've put almost 50K on it since switching it to a 5 speed. Only other thing I've noticed is my dramatic increase in mpg's. I went from about 24, to a consistent 30-31. Well worth the conversion IMHO...:laugh2:
 
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