Looking for PCM options

[Red383]

Last week I picked up a 5.7 Hemi/8HP70 drop out of a 2015 Dodge Charger. Supposed to have 60k miles on the engine/trans. I don't currently have a project car ready to drop this stuff into, but I would like to get it started/running on a stand.

I got the wiring harness with the engine, but no PCM. Looks like I can pick up a PCM from the wrecking yard for around $100, but I am not sure that will get me anywhere.

What is my best option to get a engine controller I can use to get this thing fired up?

I looked at hotwireauto, $550 for a user computer, sublimeparts, has an unlocked PCM for $450 (when available) or will unlock my computer for $300. Although I have emailed them multiple times and have gotten no response.

Or do I just break down and buy a Mopar crate kit for $1500. I cannot seem to find just the Mopar Crate PCM for sale without the rest of the kit.

I kind of want to try my hand at making the factory wiring run the engine, but I need a PCM to do this.

Any Suggestions?

Thanks

 

[67Dart273]

Frankly if you have none, and want to go with a factory computer, I would find the best deal I can with someone such as hotwire. You need to decide if you are going to use a factory computer controlled auto, or stick or an earlier "non computer" auto

 

[DionR]

Here is the best solution I know of if you already have the engine harness:

2015-2023 Car R2 QuickRun Hemi Harness

Tech Specs Plug and Play into your existing Hemi engine harness Wire Ends labeled so you know where to connect (12V+, Ground, Fuel Pump, Starter, etc.) Designed 100% by DIYHEMI, for maximum protection against abrasion and high temps in the engine bay. All of our products come with the best...

sublimeparts.com

Not sure if the 8HP plug is part of the engine harness though. Nor what else you will need to make it work. Pretty sure Sound German Engineering has a setup to make them work with the factory PCM though.

Without the above kit you will need relays and such.

You still need the PCM though. I would buy the one from the yard and have Sublime do the Crate Motor tune on it.

I know you haven't had much success contacting them, but I know others have. You might try FB, I know he is on there.

 

[DionR]

I should add that a factory PCM for 2015 and later has logic for a start signal over the CANBus that can't just be turned off. The Crate Motor tune that Sublime does makes the PCM the same as the one that Mopar sells with their swap kit, and removes this. No idea if Hotwire can do the same thing, but I would bet they can. Either way, you will need to probably get this done somehow if you buy a used PCM.

 

[Red383]

I think I want to stick with the factory ECM

By the time I buy a used ECM ($100) + sublime programing ($400), + sublime quick run harness ($900) = $1400

Mopar Hemi Crate kit with new wiring harness and ECM = $1447

Ends up being the same price.

The 8HP will be separate no matter which ECM I go with.

 

[DionR]

I completely understand. I struggle with spending a bunch of money on that stuff instead of using it for swap parts and such.

If you want to stick to the GPEC2A that matches your harness, you are stuck having to do something to remove the CANBus start option like having Sublime or Hotwire flash it. Then you could build your own power harness with the missing PCM plug, body harness plug, a PDC and wiring diagrams.

Another option would be to ditch the stock harness and retrofit an NGC setup. The cam and crank sensors have to be swapped but after that everything should plug in and work, as I understand it. You could even start with a harness from an older Hemi like an '08, but you would have to add the VVT wires and check the pinouts to make sure nothing moved around. And if you wanted to run a 6.4 intake, you could add the SRV plug as well. Note that the car NGC can't seem to make the SRV work, so you have to either run a truck NGC or an RPM window switch.

Note that there are some tuning issues to get it running with the NGC as well, but it's all stuff you could do with an HPTuner's setup if you wanted. Actual tuning is beyond my plans but I should be able to turn of SKIM and the start signal over the CANBus if I wanted to.

I looked at the differences between the NGC and GPEC2/A controllers when I was trying to pick a direction. The NGC is older and slower, but easier to deal with since it doesn't have need an SSR (Start Signal Replicator) or a crate motor flash. At the same time, the NGC can't control the radiator fans like the GPEC2A can. In the end, I decided to run the NGC for my swap.

If you were going to try and run the 8HP off the stock PCM (if it was even possible), you couldn't do the NGC controller. But if that is going to be separate anyways, you have the option open.