I've read countless threads about the Dodge ETC system and how to tweak (trick it) into achieving improved throttle response. Implementing these methods such as altering the DD tables, flywheel % power, throttle body airflow etc have definitely helped and slightly enhanced the response on my 3.6/NAG1 Sprintex S/C'd Pentastar. However, I'm still finding the part throttle response vague, jumpy and somewhat disconnected from the actual pedal input.
While I can (just) live with this type of response onroad under normal driving conditions, it becomes absolutely woeful offroad! This is where predictable throttle response throughout the whole pedal range is crucial, especially when it comes to technical driving such as rock crawling.
The 2 major problems I have observed so far is that with a fixed pedal position, the actual throttle blade opening also seems to be dependent on (1) RPM, and (2) aircharge/manifold pressure/pressure ratio. Eg: the throttle opening increases with RPM and with aircharge/manifold pressure/pressure ratio irrespective of the pedal position. This makes it very difficult to drive as you always have to alter the user input to the system (the pedal) to try and compensate. This is further compounded with the NAG1 somewhat shifting at will.
So, does anyone know exactly how this Dodge (I assume torque-based request) ETC system works and what tables/parameters I need to target to gain predictable throttle control? I'm hoping that the people in the know could chime in with their 2c.
From researching various threads, I suspect the ETC system works as follws: (Please correct me if I'm wrong)
1. Pedal % Power Request - [ECM] 35060. Pedal voltage vs NVRatio (RPM/VSS) requests a driver demanded power %
2. Power % Request (Flywheel) - [ECM] 34542. Takes the driver demanded pedal % request and RPM to request a % of the maximum available torque.
3. Indicated Aircharge to Torque per Cylinder - [ECM] 19645. This is the maximum torque per cylinder model. The torque request is determined by applying the power % request flywheel to this maximum torque.
4. Friction Torque - [ECM] 12882. Friction torque losses are added to the torque request to get a total torque request. *(not too sure on this one)*
So now we have our torque request per cylinder. Multiply by the number of cylinders to get the engine torque request. According to the HPT info bar this torque request then gets converted to an airflow request by:
Airflow = (Torque - Offset) / Factor or according to 06300CSRT8 it may actually be: Airflow = (Torque/Factor) - Offset https://forum.hptuners.com/showthrea...ue-Correlation
using:
5. Torque/Airflow Factor Offset - [ECM] 44386. Torque offset by RPM vs PRatio.
6. Torque/Airflow Factor - [ECM] 35032. Torque to airflow conversion factor by RPM.
From this airflow request I believe that the throttle body opening (voltage) is determined by the following throttle volts vs mass airflow tables which have to be equal and inverse to each other.:
7. ETC Throttle Body Airflow - [ECM] 35035
8. Desired Throttle Small Range - [ECM] 44388
9. Desired Throttle Large Range - [ECM] 44387