Hemi Truck Club banner

Megasquirt

40K views 310 replies 21 participants last post by  charged392 
#1 ·
Reading about the Megasquirt it sounds like it has a lot of capabilities. I still don't know if it is a complete answer or not. But thought it might be helpful to have a single thread to keep track of what is known about it. I have emailed them to see if there a kit already available for an 03. I'll post what I find. Anyone who has experience or information it would be great to hear about what you have done.
 
#2 ·
To run the engine alone the ms3 will work great as for trans control that's where the issue is if you swap to a 4l80e they have a kit to control that then you would be 100% shandalone and tunable at your house provided you know what your doing

I have used megasquirt on a previous vehicle I owned and was spinning it up to 9k whitout any issues and it was a turbo engine so the ms can and will work now just getting it teed into our trucks will be the trick
 
#3 ·
Sorry - I saw this thread title and thought it was about an adult film...
 
#4 ·
Mark, I know what you mean. When I first googled it, I figured I'd find one or two interesting sites. As for the MS, it looks to me we would need to install it parallel to the OEM pcm to maintain dash, speedo, AC, lights, multifunction switch, cruise and trans (TCM) input. MS3 will support knock sensors, fuel pump, sequencel injection, eliminate waste spark, w/m injection, nitrous (2stage), launch rpm limiter,idle adjust and a ton of other cool features. Cost for diypnp unit is around $650, plus cables and nice to have Megasquirter stimulator, shich being as old as I am is really needed. Still IMO not bad compared to buying a tuner/cmr tune, plus it also replaces rpm window switches. 03's may even have an advantage with having a separate TCM.
 
#5 ·
True forgot about the 03 separate tcm it may be really easy to hook that up and still have the trans work without issues in the late 04-current we would have to figure something out or chane trans out for sure either way like you said it is a good little standalone for its price and tuning it is free that's the best part just watch for cops
 
#8 ·
Sorry - I saw this thread title and thought it was about an adult film...
 
#9 ·
Another function our PCM does that is often forgotten is it regulates the battery voltage. I don't think MS addresses this, so its another reason to run it parrallel.
 
#10 ·
#11 ·
Here is the link to installing the Megasquirt3 in a modern hemi. They said they have installed one on a charger. It had to be installed parrallel to keep accessories running.
http://www.diyautotune.com/tec...uirt_in_parallel.htm

Since we have several PCM versions running our trucks, each version would need to be a little different. It mentions and I suspect they are right to run without codes/limp mode the OEM injectors and ignition outputs will need to be connected to dummy boards to simulate actual operations. I think this can be done and have not found anything really to prevent an install. Cost wise it looks like $645 for the latest MS3 ECM, $89x2 for two quad ignition boxes, $59 for a test stimulatator and $9.50 for a power supply for the stumulator. Computer connection cable. Materials needed to build the dummy boxes ??. Still IMO this is a way cool setup.
 
#12 ·
The MS stuff is really cool.

I would caution you to find out if anyone has done it on an 03 Ram specifically, as they really are that different, as I'm sure you are aware.

The PCM does not even control the ETC, which will likely be a problem, unless it allows converting to a cable TB, which would be really cool
 
#13 ·
Originally posted by charged392:
True forgot about the 03 separate tcm it may be really easy to hook that up and still have the trans work without issues in the late 04-current we would have to figure something out or chane trans out for sure either way like you said it is a good little standalone for its price and tuning it is free that's the best part just watch for cops
would the early 04s be like the 03s? I been confused on what changed mid year 04 was it the tb an toner ring changed or the computers changed mid year too?
 
#16 ·
My laptop has crashed so I'm without my 03 truck data. But running MS3 in parallel seems to solve the initial trans management issues regardless if it is a later internal TCM or a separate 03 TCM. The 03 uses a APPS that is somewhat large and primitive (go figure) compared to the later module that is part of the throttle assembly. I have been told and read where the newer APPS module can be easily installed on a 03 as a replacement unit, regardless it simply converts mechanical throttle movement to an electrical output back to the PCM as one of many other inputs to determine air/fuel and idle settings. I've posted on the MS support forum to see if anyone has done a modern hemi install and so far I've not heard from anyone. With the complexity of the dodge electronics it will come down to if the OEM PCM will play nice with a MS installed. I like DIY and this difinitely falls into that category.
 
#17 ·
A little bit of confusion going on here, hopefully I can clear a few things up.

I'll start with the '03 PCM, it controls everything engine related including the electronic throttle-body. The separate TCM controls the transmission using signals sent from the PCM, so the TCM can be physically removed with no effect on the engine, performance wise. Unlike the newer models that have the accelerator pedal position sensor mounted on the actual pedal, '03 trucks have a short cable from the pedal to a remote position sensor mounted under the battery tray. As far as I know, both accelerator position sensors provide the same signal regardless of where they are mounted. The throttle blade position comes from the throttle body on all Hemi engines.

Mopar sells a mechanical throttle body with sensors that should work with the MS3. (provided for Hemi crate engines)

The trucks switched from JTEC to NGC mid '03. In '04 and '05 they still used the exact same NGC, just without the separate TCM and also upgraded the crank toner wheel. My May '04 built 2003 Ram has the NGC computer and TCM with the transmission connectors left blank on the PCM. Pretty sure Chrysler was just using up old parts left on the shelf. (Use all the old JTEC computers until they ran out, then start using the new NGC computers with the old TCMs, until they ran out.) It drives me crazy that Chrysler switches vendors mid production run multiple times and the model year has no importance. This is why I will never have another Chrysler project.
 
#18 ·
Originally posted by FrostKing:
A little bit of confusion going on here, hopefully I can clear a few things up.

I'll start with the '03 PCM, it controls everything engine related including the electronic throttle-body. The separate TCM controls the transmission using signals sent from the PCM, so the TCM can be physically removed with no effect on the engine, performance wise. Unlike the newer models that have the accelerator pedal position sensor mounted on the actual pedal, '03 trucks have a short cable from the pedal to a remote position sensor mounted under the battery tray. As far as I know, both accelerator position sensors provide the same signal regardless of where they are mounted. The throttle blade position comes from the throttle body on all Hemi engines.

Mopar sells a mechanical throttle body with sensors that should work with the MS3. (provided for Hemi crate engines)

The trucks switched from JTEC to NGC mid '03. In '04 and '05 they still used the exact same NGC, just without the separate TCM and also upgraded the crank toner wheel. My May '04 built 2003 Ram has the NGC computer and TCM with the transmission connectors left blank on the PCM. Pretty sure Chrysler was just using up old parts left on the shelf. (Use all the old JTEC computers until they ran out, then start using the new NGC computers with the old TCMs, until they ran out.) It drives me crazy that Chrysler switches vendors mid production run multiple times and the model year has no importance. This is why I will never have another Chrysler project.
Brother good information. My March/03 built truck has the NGC with seperate TCM. I did not know it would run with the TCM pulled. Since my truck is a street truck, I want Cruise and AC working along with gauges, lights and other accessories. I know you have one of the most modified 03's out there and there is little you haven't done with it so let me ask if unplugging the OEM injectors and ignition coils will require using a dummy board to simulate their presence. Obviously I'm looking a parrallel install with MS3 running the fuel/ignition and the OEM PCM running everything else.
Your input is greatly appreciated, seems I been following your advice for years with good results.
 
#19 ·
Originally posted by Redtruck-VA:
Originally posted by FrostKing:
A little bit of confusion going on here, hopefully I can clear a few things up.

I'll start with the '03 PCM, it controls everything engine related including the electronic throttle-body. The separate TCM controls the transmission using signals sent from the PCM, so the TCM can be physically removed with no effect on the engine, performance wise. Unlike the newer models that have the accelerator pedal position sensor mounted on the actual pedal, '03 trucks have a short cable from the pedal to a remote position sensor mounted under the battery tray. As far as I know, both accelerator position sensors provide the same signal regardless of where they are mounted. The throttle blade position comes from the throttle body on all Hemi engines.

Mopar sells a mechanical throttle body with sensors that should work with the MS3. (provided for Hemi crate engines)

The trucks switched from JTEC to NGC mid '03. In '04 and '05 they still used the exact same NGC, just without the separate TCM and also upgraded the crank toner wheel. My May '04 built 2003 Ram has the NGC computer and TCM with the transmission connectors left blank on the PCM. Pretty sure Chrysler was just using up old parts left on the shelf. (Use all the old JTEC computers until they ran out, then start using the new NGC computers with the old TCMs, until they ran out.) It drives me crazy that Chrysler switches vendors mid production run multiple times and the model year has no importance. This is why I will never have another Chrysler project.
Brother good information. My March/03 built truck has the NGC with seperate TCM. I did not know it would run with the TCM pulled. Since my truck is a street truck, I want Cruise and AC working along with gauges, lights and other accessories. I know you have one of the most modified 03's out there and there is little you haven't done with it so let me ask if unplugging the OEM injectors and ignition coils will require using a dummy board to simulate their presence. Obviously I'm looking a parrallel install with MS3 running the fuel/ignition and the OEM PCM running everything else.
Your input is greatly appreciated, seems I been following your advice for years with good results.
Cruise control will definitely be off the table as everything needs to be 100% perfect according to the PCM. Even some unmodified trucks drop out of cruise from small electrical gremlins.

I think the dash and lights (BCM) would still work if all the engine sensors were disconnected from the PCM. It would just seem like the engine was not running. An externally regulated alternator may be needed and a few bypasses to activate the starter and fuel pump. Shouldn't be too difficult. My truck is practically there already. Ignition and fuel injectors are solely run off my aftermarket controller, just using the factory spark and injector signals for reference even though they don't actually run anything. Basically a hybrid between a typical piggyback and full standalone controller. This way I have no engine codes and have full cruise control, a/c (if it was still there)
 
#20 ·
Originally posted by FrostKing:
A little bit of confusion going on here, hopefully I can clear a few things up.

I'll start with the '03 PCM, it controls everything engine related including the electronic throttle-body. The separate TCM controls the transmission using signals sent from the PCM, so the TCM can be physically removed with no effect on the engine, performance wise. Unlike the newer models that have the accelerator pedal position sensor mounted on the actual pedal, '03 trucks have a short cable from the pedal to a remote position sensor mounted under the battery tray. As far as I know, both accelerator position sensors provide the same signal regardless of where they are mounted. The throttle blade position comes from the throttle body on all Hemi engines.

Mopar sells a mechanical throttle body with sensors that should work with the MS3. (provided for Hemi crate engines)

The trucks switched from JTEC to NGC mid '03. In '04 and '05 they still used the exact same NGC, just without the separate TCM and also upgraded the crank toner wheel. My May '04 built 2003 Ram has the NGC computer and TCM with the transmission connectors left blank on the PCM. Pretty sure Chrysler was just using up old parts left on the shelf. (Use all the old JTEC computers until they ran out, then start using the new NGC computers with the old TCMs, until they ran out.) It drives me crazy that Chrysler switches vendors mid production run multiple times and the model year has no importance. This is why I will never have another Chrysler project.
...confusion...?
There is no way to control the ETC through the PCM on an 03, which you can do on an 04...
 
#21 ·
Originally posted by Mike@Diablosport:
The PCM in the 03 model does not control the Electronic Throttle, (has a separate module for that) which is why there are no tuning adjustments for idle speed, or speed limiter/rev limiter. Thats the biggest difference in the 03s vs 04's+ that I am aware of...
Mike this is from the 03 service manual:
The Accelerator Pedal Position Sensor (APPS) is a linear potentiometer. It provides the Powertrain Control Module (PCM) with a DC voltage signal proportional to the angle, or position of the accelerator pedal. The APPS signal is translated (along with other sensors) to place the throttle plate (within the throttle body) to a pre-determined position.

The PCM clearly controls the throttle using the APPS sensor input and others. DSP's inabiity to adjust 03's speed, rpm limits and their problems with tire size adjustment is IMO only an indication of their lack of understanding the early (NGC) PCM.

The more I read about the Megasquirt the more convinced I am this will do a lot for tuning our Rams, althrough like a lot of performance stuff we have been over looked compared to the other makes. I'll keep posting what I find.
 
#22 ·
Originally posted by Redtruck-VA:
Originally posted by Mike@Diablosport:
The PCM in the 03 model does not control the Electronic Throttle, (has a separate module for that) which is why there are no tuning adjustments for idle speed, or speed limiter/rev limiter. Thats the biggest difference in the 03s vs 04's+ that I am aware of...
Mike this is from the 03 service manual:
The Accelerator Pedal Position Sensor (APPS) is a linear potentiometer. It provides the Powertrain Control Module (PCM) with a DC voltage signal proportional to the angle, or position of the accelerator pedal. The APPS signal is translated (along with other sensors) to place the throttle plate (within the throttle body) to a pre-determined position.

The PCM clearly controls the throttle using the APPS sensor input and others. DSP's inabiity to adjust 03's speed, rpm limits and their problems with tire size adjustment is IMO only an indication of their lack of understanding the early (NGC) PCM.

The more I read about the Megasquirt the more convinced I am this will do a lot for tuning our Rams, althrough like a lot of performance stuff we have been over looked compared to the other makes. I'll keep posting what I find.
I like that spin, thats cool. LOL.

We know more about the NGC than ANYONE in the business. I will assure you that despite what you manual tells you, the 03 uses a separate module for the ETC.

Tire size has been working for years, and is not even part of the calibration, but then again, what do we know about NGC's?

Good luck with your project, not sure why I even bothered
 
#23 ·
I have replaced the entire wiring harness in the engine compartment of my truck and I can assure you the ETC is wired directly to the PCM. If there is a separate module for the ETC, it is virtual in nature. Here is how the factory has the ETC wiring. The Electronic Throttle Control Module in the diagram is the actual throttle-body.

Redtruck-VA, the APPS does not control the ETC directly or have any involvement with performance tuning. It just shows how far the gas pedal is down, the tuning will decide how far to open the throttle.

 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top