GM > Operating System



Operating System Enhancements

HP Tuners offers a number of enhanced operating systems for various applications. Detailed descriptions of each follow.

Operating System Patches

This patches only apply to the operating system you have open if they are visible. If you do not see them, they do not apply to the file you have open.


Operating System Enhancements With Real Time Tuning (RTT)

Starting with the release of VCM Suite 2.1.12 we have added Real Time Tuning to our VCM Enhancements.
What we have done is add the RTT on top of our existing VCM Enhancements. If a VCM Enhancement has support for RTT, it will display as follows:



Applying the VCM Enhancement is the same as any other.
If you already have an existing VCM Enhancement applied to your vehicle and wish to use RTT,
you will need to re-apply the VCM Enhancement with RTT from your stock GM OS.

For information on how to use our Real Time Tuning VCM Enhancements, please see the Real Time Tuning section in the help files.


1bar Speed Density Enhanced (GenIII V8)

This enhancement contains the following features:

2bar and 3bar MAP - Speed Density (GenIII V8)

This enhancement contains the following features:

NOTE: You must use a correctly calibrated 2bar MAP sensor for this application. The default MAP sensor calibration values may not be accurate for your MAP sensor.

NOTE: On 98 V8 vehicles there is no 2bar MAP PID. The SAE MAP PID has been reprogrammed to register the correct amount of boost. Also, due to the fact that the 98 Vehicles do not report an OS ID, the histograms will not automatically enlarge for boosted regions. You will need to create your own or load histograms from the saved folder. Pre-configured histograms for 98 2bar vehicles are located there.

Application Procedure (GenIII V8)

To apply the enhancement to your PCM please use the following procedure. NOTE: the procedure involves the use of the "Write Entire" process. This process is not guaranteed to be safe. Please do not attempt to write the entire VCM if you have had any trouble reading or writing the VCM in the past. If an error occurs during writing of critical operating system components and the VCM is powered down, the VCM will become unrecoverable via software methods.

  1. Start with a stock or existing tune from the PCM.
  2. Open the file in VCM Editor
  3. Select Operating System, a window will appear with choices available.
  4. Apply the relevant modification by clicking the button.
  5. When prompted, save the file under a new name something like "XYZ_2bar.bin". This is now your new "Base" file that must be used for all future tuning.
  6. The editor will automatically close the file after saving.
  7. Open the newly saved file in the editor. You should see that the operating system ID has changed from your original file.
  8. (This step for 2bar and 3bar enhancement only) The VE table will be full of invalid data. You *must* create a valid VE table before writing the file to the PCM. It is a good idea to copy your previous VE table into the non-boost region and then copy and increase the last row of the VE table to the new boost area. It is important to start tuning on the rich side (higher numbers) and then work back to your desired AFR.
  9. Save the file in the editor, you are now ready to write to the PCM.
  10. IMPORTANT: The next step involves using the "Write Entire" option. Remember this option is not 100% recoverable on failure in some circumstances. Do NOT disconnect the battery if you have problems during this next step. Once this step is completed you can use the regular "Write VCM" function for all tuning changes.
  11. Connect to the vehicle and turn on ignition, wait 10secs.
  12. Still in VCM Editor with your file open, select Flash -> Write Entire. The process takes approximately 2-4 minutes depending on vehicle type.
  13. When the write is completed, turn off ignition and wait 30secs.
  14. Turn on ignition, wait 10secs.
  15. The PCM should display the new operating system ID. (Not available on GM 98 V8 vehicles)
  16. At this point the VCM should be now running the new operating system and you can now use the regular and safe "Write VCM" for all future tuning changes.
  17. Do not perform steps 17 and 18 if you are running 2bar on a GM 98 V8 vehicle. The SAE MAP PID has been reconfigured in the OS for your vehicle to read properly.
  18. (This step for 2bar and 3bar enhancement only) Open VCM Scanner and connect to the vehicle. Open the Table display (Scan -> Table Display). Right-click the "Manifold Air Pressure (SAE)" PID and select "Delete". This removes the existing 1 bar PID from the table, if you don't do this the histogram will not function correctly.
  19. (This step for 1/2/3 bar Speed Density enhancements only) Right-click the "Mass Air Flow(SAE)" PID and select "Delete". This removes the existing MAF PID, if you don't do this the histogram will not function correctly.
  20. (This step for 2bar and 3bar enhancement only) Right-click again on the table display cell and select "Insert", go to the Engine -> Airflow section and choose either the "Manifold Air Pressure - 2 bar" or "Manifold Air Pressure - 3 bar" PID, double-click to insert it into the table.
  21. (This step for 2bar and 3bar enhancement only) Save the new scanner configuration using File -> Save Config.
  22. You are now ready to tune using your new enhanced PCM.


2.5 Bar MAP - Speed Density (LS2 V8 - E40 ECM)

This enhancement contains the following features:

NOTE: The default MAP Sensor linear and offset values are set for common 2bar MAP sensors.

NOTE: The largest MAP sensor the E40 ECM will support is 2.5 bar.

Application Procedure (LS2 E40 ECM)

To apply the enhancement to your PCM please use the following procedure.

  1. Start with a stock or existing tune from the PCM.
  2. Open the file in VCM Editor
  3. Select Operating System, a window will appear with choices available.
  4. Apply the relevant modification by clicking the button.
  5. When prompted, save the file under a new name something like "XYZ_2bar.bin". This is now your new "Base" file that must be used for all future tuning.
  6. The editor will automatically close the file after saving.
  7. Open the newly saved file in the editor. You should see that the operating system ID has changed from your original file.
  8. The new Boost VE table will be full of zero data. You *must* create a valid VE table before writing the file to the PCM.
  9. During all times it is important that you keep the 105 kPa column in the Main VE table the same as the 105 kPa column in the Boost VE table (if you change one, change the other). If you don't, the transition from one table to the next may not be smooth.
  10. The new rescaled fan temperature axis will mean the fans will switch on at lower coolant temperatures than stock. If you wish the fans to operate at the stock on/off temperatures you need to modify this table.
  11. Save the file in the editor, you are now ready to write to the PCM.
  12. IMPORTANT: The next step involves using the "Write Entire" option. Once this step is completed you can use the regular "Write VCM" function for all tuning changes.
  13. Connect to the vehicle and turn on ignition, wait 10secs.
  14. Still in VCM Editor with your file open, select Flash -> Write Entire. The process takes approximately 2-4 minutes depending on vehicle type.
  15. When the write is completed, turn off ignition and wait 30secs.
  16. Turn on ignition, wait 10secs.
  17. The PCM should display the new operating system ID.
  18. At this point the VCM should be now running the new operating system and you can now use the regular and safe "Write VCM" for all future tuning changes.
  19. Open VCM Scanner and connect to the vehicle. Open the Histogram display (Scan -> Histogram Display).
  20. Select an unused histogram configuration and choose "Import Histogram" (the folder icon), load one of the following files: "VE Boost - AFR Error (LS2 2bar).hst", "VE Boost - Narrowband O2's (LS2 2bar).hst" or "VE Boost - Wideband (LS2 2bar) O2.hst" (there are three pre-configured histograms depending on your tuning method). This allows you to log AFR related values used to tune the Boost VE table.
  21. Save the new scanner configuration using File -> Save Config.
  22. You are now ready to tune using your new enhanced PCM.


2.5 Bar MAP - Speed Density (E38 ECM - LS2 and other engines)

This enhancement contains the following features:

The MAF High Freq table has been rescaled to allow up to 15400Hz at 300 Hz resolution and the maximum airflow limit for this table has also been adjusted to allow up to 1024 g/sec (instead of the stock 512 g/sec). You must populate this table for the engine to run at moderate speeds with the MAF enabled. An easy way to do this is to copy the values that line up from the old table (every 4th value) and then interpolate/smooth between values. Please note that although the table now extends up to 15400 Hz, the stock MAF may not function accurately at such high airflows nor may it be able to actually output such high frequencies accurately, you may need a differnt MAF or aftermarket unit to achieve this high range.

There are three new VE tables. Two Normal tables (one for the intake manifold control open and the other for closed) and one Displacement On Demand (DoD) VE table. For vehicles that do not have inatke manifold control and/or DoD it is a good idea to set all three VE tables the same. The VE tables are empty by default, you need to populate the VE tables before use even if you plan to use the MAF (the VE tables are used during MAF mode as well). The VE multiplier tables can be used to change (multiply) the VE value based on Charge Temperature (Manifold Air Temperature) and TPS/RPM. The TPS Multiplier table can be useful for tuning large camshafts. On various tables the RPM/MAP/TPS axes are configurable, you can set the resolution to suit your application. The defaults are suited up to around 10psi boost (175 kPa) with 5 kPa MAP resolution and 200 RPM resolution from 400-6800 RPM.

Boost enrichment functions as per our other enhancements, with and enable MAP, hysteresis and Boost Enrich table. Boost enrichment also triggers open loop fuelling. The ECM will use the richest of the PE table and the Boost Enrich table values when fuelling.

The new Boost Fuel Cut feature will cut fuel to all cylinders whenever boost is above the enable MAP value. There is also an enable/disable option for this feature. It is a complete fuel cut to all cylinders when active. Note: in VCM Scanner the Fuel Cut Type PID will report "Flood" as the type when the boost fuel cut is activated.

NOTE: The default MAP Sensor linear and offset values are set for common 2bar MAP sensors, you may need to adjust these values for your particular sensor. If you plan to use the enhancement for non-boosted applications you will need to return the MAP Sensor Linear/Offset values to stock (typically 94.43/10.33 for a GM 1bar sensor).

NOTE: The largest MAP sensor the E38 ECM will support is 2.5 bar (255 kPa).

Application Procedure (E38 ECM)

To apply the enhancement to your PCM please use the following procedure.

  1. Start with a stock or existing tune from the PCM.
  2. Open the file in VCM Editor
  3. Select Operating System, a window will appear with choices available.
  4. Apply the relevant modification by clicking the button.
  5. When prompted, save the file under a new name something like "XYZ_2bar.bin". This is now your new "Base" file that must be used for all future tuning.
  6. The editor will automatically close the file after saving.
  7. Open the newly saved file in the editor. You should see that the operating system ID has changed from your original file.
  8. The 3 new VE tables and the MAF High Freq tables will be full of zero data by default. You *must* enter valid data in these tables before writing the file to the PCM.
  9. During all times it is important that you keep the 5800 Hz cell in the MAF High Freq table the same as the MAF Low Freq table cell, otherwise the transition between tables will not be smooth.
  10. The new rescaled fan temperature axis will mean the fans will switch on at lower coolant temperatures than stock. If you wish the fans to operate at the stock on/off temperatures you need to modify this table.
  11. Save the file in the editor, you are now ready to write to the PCM.
  12. IMPORTANT: The next step involves using the "Write Entire" option. Once this step is completed you can use the regular "Write VCM" function for all tuning changes.
  13. Connect to the vehicle and turn on ignition, wait 10secs.
  14. Still in VCM Editor with your file open, select Flash -> Write Entire. The process takes approximately 2-4 minutes depending on vehicle type.
  15. When the write is completed, turn off ignition and wait 30secs.
  16. Turn on ignition, wait 10secs.
  17. The PCM should display the new operating system ID.
  18. At this point the VCM should be now running the new operating system and you can now use the regular and safe "Write VCM" for all future tuning changes.
  19. Open VCM Scanner and connect to the vehicle. Open the Histogram display (Scan -> Histogram Display).
  20. Select an unused histogram configuration and choose "Import Histogram" (the folder icon), load one of the following files: "VE Boost - AFR Error (LS2 2bar).hst", "VE Boost - Narrowband O2's (LS2 2bar).hst" or "VE Boost - Wideband (LS2 2bar) O2.hst" (there are three pre-configured histograms depending on your tuning method). This allows you to log AFR related values used to tune the Boost VE table.
  21. Save the new scanner configuration using File -> Save Config.
  22. You are now ready to tune using your new enhanced PCM.


Warning

Use these enhancements at your own risk. Modifications can result in permanent destruction of vehicle components. Any modifications that change vehicles emissions from stock form (most modifications do this) are not allowed by the EPA and are to be used for off-road use only. Modifying or removing any emissions testing is illegal and subject to heavy fines. HP Tuners LLC is not liable for any type of damage caused by use of these enhancements. Use at your own risk!