NGC or GPEC2?

[DionR]

Anyone have any insight into any advantages the 2011+ GPEC2 PCM has over the 2012 and older NGC PCM?

Picked up a 2017 or 2019 core 5.7 longblock last night and trying to decide which controls of the OEM variety would be the better direction. Motor only, so kind of starting over as far as controls anyway.

I already know that the motor I have won't run under an NGC controller due to the wrong crank tone ring. I'm thinking I might be able to swap it if the NGC setup has enough going for it, but could be I am wrong about that. I'm assuming it is possible since Hotwire Auto doesn't mention anything about it and uses a 2010 Ram PCM for 2009+ motors.

I am also aware of the SKIM and need for an SSR with the GPEC2. And that a 2015+ PCM needs to be unlocked.

I'm not opposed to running a Holley or MS setup. Just trying to narrow it down some if I "roll my own".

 

[67Dart273]

LOL ya lost me at NG.................

 

[DionR]

LOL ya lost me at NG.................

I admit, I am still trying to get it all straight in my head.

 

[DionR]

Maybe something to add to this question. AC controls?

Best guess is that the GPEC2 unit controls the AC clutch based on input on the CanBUS network. Does the NGC unit do it the same way?

Not the end of the world, just something I am trying to wrap my mind around. Spent some time looking at AC compressors and such and (I think) the Holley mounts coupled with the short compressor like from a Ram might actually bolt up. Which brings up the question of how to control it.

 

[royslead]

Guess it depends on what you want it to do. GPEC allowed for more integration and features, among other things that do and do not have to do with running the engine and trans. As for your AC issue, why not get away from computer controlled lsd's and just revert it to a manually controlled, clutch cycling switched system? I'm all for conversions, but with a lot of this stuff it can be pretty tricky if you aren't going to incorporate the whole system. In those cases, I would try to keep it as simple as possible.

 

['68cuda416]

Maybe something to add to this question. AC controls?

Best guess is that the GPEC2 unit controls the AC clutch based on input on the CanBUS network. Does the NGC unit do it the same way?

Not the end of the world, just something I am trying to wrap my mind around. Spent some time looking at AC compressors and such and (I think) the Holley mounts coupled with the short compressor like from a Ram might actually bolt up. Which brings up the question of how to control it.

These type questions for example AC clutch control can be answered by either wiring diagrams and or also factory or also aftermarket service information as in ALLDATA or Mitchell On Demand or other user platforms but that way you can investigate your concerns for the exact year make model you are wondering about.

 

[DionR]

As for your AC issue, why not get away from computer controlled lsd's and just revert it to a manually controlled, clutch cycling switched system?

I guess I was thinking that if I already had a computer in place, why not use it to control the AC (if possible). What I don't want to have to add another module, guess I will have to look further into it.

Honestly, AC knowledge is fairly weak for me beyond the basic principle of how it works. But I think most OEM EFI systems control the AC clutch so it can do thinks like turn it off when you go to full throttle. Could be that is all they do, don't know. Further research required.

Thanks.

 

[DionR]

These type questions for example AC clutch control can be answered by either wiring diagrams and or also factory or also aftermarket service information as in ALLDATA or Mitchell On Demand or other user platforms but that way you can investigate your concerns for the exact year make model you are wondering about.

I appreciate that, good point.

FWIW, I did look at the pinout I have for the NGC controller and don't see an "AC on" input. But not everything is labeled so it could be there.

Thanks.

 

[DionR]

In regards to by original question, here's a point ran across since I asked it.

The SSR module appears to be a must in most situations. And it is an unadvertised module that runs something like $250. In my mind, this makes a stock GPEC2 PCM a problem. Seems that no one has figured out how to turn that off in the PCM, at least as far as I have found. The only other option appears to be DIYHemi saying they can turn a GPEC2 PCM into a crate motor PCM which removes the requirement.

 

['68cuda416]

I appreciate that, good point.

FWIW, I did look at the pinout I have for the NGC controller and don't see an "AC on" input. But not everything is labeled so it could be there.

Thanks.

I can't answer that without knowing exactly the year, make, model, engine size your referring to

 

[DionR]

I can't answer that without knowing exactly the year, make, model, engine size your referring to

Ah, gotcha. I guess I was looking more for a general idea if anyone knew. Since I don't have anything at all right now it is hard to give specifics.

If I were to go with an NGC controller, it would probably out of a 2010 Ram or similar. Those come with the SRV control and seem to be the default application when others do this.

Don't feel like you need to go do a bunch of research for me. I am capable, just asked to see if anyone had any personal knowledge.

 

['68cuda416]

Ah, gotcha. I guess I was looking more for a general idea if anyone knew. Since I don't have anything at all right now it is hard to give specifics.

If I were to go with an NGC controller, it would probably out of a 2010 Ram or similar. Those come with the SRV control and seem to be the default application when others do this.

Don't feel like you need to go do a bunch of research for me. I am capable, just asked to see if anyone had any personal knowledge.

Without actual specifics all your gonna get is opinions of this or that and probably will be wrong anyway.

 

[DionR]

These type questions for example AC clutch control can be answered by either wiring diagrams and or also factory or also aftermarket service information as in ALLDATA or Mitchell On Demand or other user platforms but that way you can investigate your concerns for the exact year make model you are wondering about.

Just a note, wiring diagrams might not tell someone much, hopefully the service manual does though. So much of the controls on the later cars are done via the CanBus network which can't be communicated on the diagrams.

Used to be the computer needed inputs to tell it when things should be turned on, but now it just monitors the CanBus and sees the message "AC on" and so it closes the AC compressor relay. Similarly, the issue with needing the SSR (Start Signal Replicator) is due to the security module putting a message on the CanBus network that says it is ok for the vehicle to run, and until the PCM reads this it won't allow the motor to start. So now some setups require a module that replicates that same message and puts it on the network, just to trick the PCM into thinking things are ok.

I went and looked at a 2001 Ram service manual and the JTEC PCM has 2 AC inputs. The heater controls put power on a line that is branched with one going direct to the PCM and the other passing through the high and low switches before also going to the PCM. When the PCM sees power on both pins, it engages the AC compressor depending on the logic it has. This is very easy to replicate in an early car, just flip a switch and let the PCM take care of it.

I was hoping at least the NGC PCM would work similarly, but based on the pinouts it appears there are no AC inputs. So I have to guess that by then they were reading the CanBus for AC status. Not sure even where that comes from on a 2010 Ram, can't tell if there is a BCM, but I can see that the heater/ac controls are on the CanBus network, so it probably is direct from the controls. Not interested in fitting the Ram heater controls to my car, so not sure the answer right now.

My only concern with going old school is turning it off when going to full throttle. Seems like a useful feature, but maybe the original setup didn't do that so might not be the end of the world.

 

[DionR]

...why not get away from computer controlled lsd's and just revert it to a manually controlled, clutch cycling switched system?

Just a comment. It's not that I am looking to make everything computer controlled, just seems like if something has logic built in to control something why not make use of it?

You have to admit that there are things that are easier to control using logic rather than a bunch of mechanical switches. For example, if you wanted to build in a safety feature that disables AC based on engine temp and RPM, you would have to add a temperature switch and some kind of RPM switch. That's two more modules and several feet of wire in addition to the already existing high and low switch. On the other hand, if you already have a module in the car that is making use of both of those readings, it is easy to let it control the AC compressor and disconnect it when one or both those thresholds are reached.

Now I admit that at some point that become even more complicated when you have 120+ wires running to a PCM. Which is why they put a bunch of info on a network now and let the modules that need it read and use what it needs. So now instead of a wires carrying info like vehicle speed, AC request, tow mode, transmission gear, cruise set/resume/cancel, etc, you have two small wires carrying all of it.

Another way to look at it is, my setup will almost certainly have the CanBus prewired in just because you need it to tune the computer via the OBD2 port. So if later on I figure out what the AC request message is, I could setup an ardino that would broadcast it on the CanBus network when I close a switch. Now I can add that module under the dash and I don't have any extra wires to run through the firewall, or to the PCM, beyond anything I need to run from the PCM to close the AC compressor clutch.

I could see that module do a couple of things, too. If the setup still needs the SSR, I could see a hidden button that if not pressed doesn't allow the car to start. I could also see that if there is a "tow mode" option, setting up parameters to create something like a nitrous tune, or cruise mode, or something similar so that the motor runs different based on the push of a button. The last might not be available, but what if it was.

 

['68cuda416]

Just a note, wiring diagrams might not tell someone much, hopefully the service manual does though. So much of the controls on the later cars are done via the CanBus network which can't be communicated on the diagrams.

Used to be the computer needed inputs to tell it when things should be turned on, but now it just monitors the CanBus and sees the message "AC on" and so it closes the AC compressor relay. Similarly, the issue with needing the SSR (Start Signal Replicator) is due to the security module putting a message on the CanBus network that says it is ok for the vehicle to run, and until the PCM reads this it won't allow the motor to start. So now some setups require a module that replicates that same message and puts it on the network, just to trick the PCM into thinking things are ok.

I went and looked at a 2001 Ram service manual and the JTEC PCM has 2 AC inputs. The heater controls put power on a line that is branched with one going direct to the PCM and the other passing through the high and low switches before also going to the PCM. When the PCM sees power on both pins, it engages the AC compressor depending on the logic it has. This is very easy to replicate in an early car, just flip a switch and let the PCM take care of it.

I was hoping at least the NGC PCM would work similarly, but based on the pinouts it appears there are no AC inputs. So I have to guess that by then they were reading the CanBus for AC status. Not sure even where that comes from on a 2010 Ram, can't tell if there is a BCM, but I can see that the heater/ac controls are on the CanBus network, so it probably is direct from the controls. Not interested in fitting the Ram heater controls to my car, so not sure the answer right now.

My only concern with going old school is turning it off when going to full throttle. Seems like a useful feature, but maybe the original setup didn't do that so might not be the end of the world.

I'm not being a smart *** or mean but I will keep it real......your comments prove to me that you are in way over your head and there is not a chance in hell that someone on here could hold your hand through this debacle you are wanting to undertake.....in my opinion you need to farm it out to those that are qualified and pay the bill and if you can't do that then just put this fantasy to bed and say goodnight.

 

['68cuda416]

Just a note, wiring diagrams might not tell someone much, hopefully the service manual does though. So much of the controls on the later cars are done via the CanBus network which can't be communicated on the diagrams.

Used to be the computer needed inputs to tell it when things should be turned on, but now it just monitors the CanBus and sees the message "AC on" and so it closes the AC compressor relay. Similarly, the issue with needing the SSR (Start Signal Replicator) is due to the security module putting a message on the CanBus network that says it is ok for the vehicle to run, and until the PCM reads this it won't allow the motor to start. So now some setups require a module that replicates that same message and puts it on the network, just to trick the PCM into thinking things are ok.

I went and looked at a 2001 Ram service manual and the JTEC PCM has 2 AC inputs. The heater controls put power on a line that is branched with one going direct to the PCM and the other passing through the high and low switches before also going to the PCM. When the PCM sees power on both pins, it engages the AC compressor depending on the logic it has. This is very easy to replicate in an early car, just flip a switch and let the PCM take care of it.

I was hoping at least the NGC PCM would work similarly, but based on the pinouts it appears there are no AC inputs. So I have to guess that by then they were reading the CanBus for AC status. Not sure even where that comes from on a 2010 Ram, can't tell if there is a BCM, but I can see that the heater/ac controls are on the CanBus network, so it probably is direct from the controls. Not interested in fitting the Ram heater controls to my car, so not sure the answer right now.

My only concern with going old school is turning it off when going to full throttle. Seems like a useful feature, but maybe the original setup didn't do that so might not be the end of the world.

You gonna turn the clutch off and on repeatedly while driving with your toggle switch.....like I said your in over your head but if you find this stuff to be of interest or your bored and curious then knock yourself out but I can guarantee you will never make work what you are trying to do on your own.

 

['68cuda416]

Just a comment. It's not that I am looking to make everything computer controlled, just seems like if something has logic built in to control something why not make use of it?

You have to admit that there are things that are easier to control using logic rather than a bunch of mechanical switches. For example, if you wanted to build in a safety feature that disables AC based on engine temp and RPM, you would have to add a temperature switch and some kind of RPM switch. That's two more modules and several feet of wire in addition to the already existing high and low switch. On the other hand, if you already have a module in the car that is making use of both of those readings, it is easy to let it control the AC compressor and disconnect it when one or both those thresholds are reached.

Now I admit that at some point that become even more complicated when you have 120+ wires running to a PCM. Which is why they put a bunch of info on a network now and let the modules that need it read and use what it needs. So now instead of a wires carrying info like vehicle speed, AC request, tow mode, transmission gear, cruise set/resume/cancel, etc, you have two small wires carrying all of it.

Another way to look at it is, my setup will almost certainly have the CanBus prewired in just because you need it to tune the computer via the OBD2 port. So if later on I figure out what the AC request message is, I could setup an ardino that would broadcast it on the CanBus network when I close a switch. Now I can add that module under the dash and I don't have any extra wires to run through the firewall, or to the PCM, beyond anything I need to run from the PCM to close the AC compressor clutch.

I could see that module do a couple of things, too. If the setup still needs the SSR, I could see a hidden button that if not pressed doesn't allow the car to start. I could also see that if there is a "tow mode" option, setting up parameters to create something like a nitrous tune, or cruise mode, or something similar so that the motor runs different based on the push of a button. The last might not be available, but what if it was.

This is the stuff right here that pisses me off and aggravates me to no end.......if you want everything computer controlled then buy a new type car and be happy.....if you don't mind the old school way of doing things that were more mechanical in design then drive and enjoy a old car for what it is.......but when people with too much time on their hands decides they are smart enough and want to try and modernize an old car with modern car technology I get really annoyed. YOU ARE IN WAY OVER YOUR HEAD......GO BACK TO THE SHALLOW PART OF THE POOL AND ENJOY THE KNEE DEEP WATER.

 

[DionR]

I'm not being a smart *** or mean but I will keep it real......your comments prove to me that you are in way over your head and there is not a chance in hell that someone on here could hold your hand through this debacle you are wanting to undertake.....in my opinion you need to farm it out to those that are qualified and pay the bill and if you can't do that then just put this fantasy to bed and say goodnight.

Hmm...guessing either I didn't communicate it well enough or I triggered you or something. I was actually trying to explain to you, not ask a question, why a wiring diagram isn't enough anymore.

 

[DionR]

You gonna turn the clutch off and on repeatedly while driving with your toggle switch.....like I said your in over your head but if you find this stuff to be of interest or your bored and curious then knock yourself out but I can guarantee you will never make work what you are trying to do on your own.

See, you missed it. The point was that I hit a switch on the dash and the PCM turns the clutch on and off as needed, just like it would in the 2010 Ram. Far as the motor/PCM/AC is concerned it is still in a truck.

BTW, there are certainly other ways to do it, I was just speculating on the power of using the existing CanBus network instead of ignoring it because it is "scary".

 

['68cuda416]

Hmm...guessing either I didn't communicate it well enough or I triggered you or something. I was actually trying to explain to you, not ask a question, why a wiring diagram isn't enough anymore.

It is enough.....that and with service information you would have all you need to know, just having one without the other will not stop progress but there will be holes or questions that the other could answer or fill.

 

['68cuda416]

See, you missed it. The point was that I hit a switch on the dash and the PCM turns the clutch on and off as needed, just like it would in the 2010 Ram. Far as the motor/PCM/AC is concerned it is still in a truck.

BTW, there are certainly other ways to do it, I was just speculating on the power of using the existing CanBus network instead of ignoring it because it is "scary".

No actually you just proved it by your response to me.....you have no idea what your talking about and how these or even simple electrical systems work. Don't let me stop you with your dream or fantasy but you will never get it to work how your envisioning in your head you think you can.

 

[DionR]

...It's not that I am looking to make everything computer controlled, just seems like if something has logic built in to control something why not make use of it?

.......if you want everything computer controlled then buy a new type car and be happy.....

See, you missed it again. Read the second part of quoted message again...if it is available, why not used it?

As to being in the deep end of the pool - maybe. I've never been one to say I can't make a mistake nor do I know what I don't know. I'm also one that seems to take way too long to get projects actually on the car. No excuses for that. But in regards to getting this motor in the car and fires, based on what I do know, pretty sure I can make it happen. AC, cruise, things like that are a different question and a bridge we will cross when we get there.

 

[DionR]

No actually you just proved it by your response to me.....you have no idea what your talking about and how these or even simple electrical systems work. Don't let me stop you with your dream or fantasy but you will never get it to work how your envisioning in your head you think you can.

No venom, honest question. Do you understand how the CanBus networks function in newer cars?

 

['68cuda416]

See, you missed it again. Read the second part of quoted message again...if it is available, why not used it?

As to being in the deep end of the pool - maybe. I've never been one to say I can't make a mistake nor do I know what I don't know. I'm also one that seems to take way too long to get projects actually on the car. No excuses for that. But in regards to getting this motor in the car and fires, based on what I do know, pretty sure I can make it happen. AC, cruise, things like that are a different question and a bridge we will cross when we get there.

You probably will get it running even if what you are utilizing needs a immobilizer delete and as far as the rest of it.........who knows, lol, good luck and enjoy your projects. I have more than I need too and understand what you mean about not getting as far along as wanted.

 

[DionR]

It is enough.....that and with service information you would have all you need to know, just having one without the other will not stop progress but there will be holes or questions that the other could answer or fill.

No argument. In theory, the service information should explain what isn't apparent on the wiring diagram.