Swap 84-85 ECM into 82CE

Kev'C3

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Feb 14, 2015
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I everyone, I hope everyone is well and nobody is going stir crazy! I have a 82 CE and was wondering if I can swap my ECM for a ECM from a 84-85 Vette? And would it be worth it? Or would help to get a performance chip or should I do both? :confused:
 
Never heard of that. It's maybe possible (the C4 is a TPI engine I think). Don't know but I think gains would be minimal.
 
I everyone, I hope everyone is well and nobody is going stir crazy! I have a 82 CE and was wondering if I can swap my ECM for a ECM from a 84-85 Vette? And would it be worth it? Or would help to get a performance chip or should I do both? :confused:

The transistor circuits in the ECMs that controls the injectors are different for a TPI and a TBI system. (Caution: Long and boring explanation ahead.)The TPI circuit uses transistors in a simple saturation mode, that uses the injector resistance to limit the current (kinda like a points ignition system where the ballast and coil resistance sum limits the primary current, and the points just act like a dumb switch). Because TBI injectors/pintles are big, they need a bunch more current to make a significant enough magnetic field to operate as a strong electromagnet to pull the pintle off its seat fast enough to work well at all RPMs. This requires ECM circuitry that runs about 4 amps through the injector to get it to open quickly, and then drops the current down to a steady one amp level to keep the injector/pintle open. You can make the TBI injectors run on a TPI ECM if absolutely necessary, but I would expect the system to operate rather shitty at high RPM.

Also, remember that the TPI system uses a mass air flow sensor to measure the airflow going into the engine, whereas the TBI system is a speed/density system, which uses the MAP sensor to measure manifold vacuum/pressure, and along with RPM the ECM calculates the airflow into the engine. Just going to be a PITA to plumb up a MAF sensor to a TBI manifold if you use an '85 ECM.

That's the highlights. Unless you have a problem with the stock '82 ECM and can't get a replacement, then an '84 ECM might be the next option. But remember, the harness connectors are different between '82 and '84, requiring a harness modification or a short adapter harness between the '82 harness and the '84 ECM.

There are guys who are using later truck TBI ECMs on their older cars, but that requires connector harness mods, and some reprogramming of the ECM. (I'm halfway through that with my '84, but other priorities keep getting in the way.)
 
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