Open Source Tuning
- 1 What is it
- 2 Who is it for
- 3 How does it work
- 4 Why should I open source tune?
- 5 What are the risks?
- 6 How can I contribute
- 7 Thats cool - but how
- 8 Getting started with a Stage X tune
What is it
Open source tuning is, generally, the use of openly available tools to tune a car. Some would argue that you can even consider it open source tuning if you're using commercial tools since we're all relying on openly shared information.
Who is it for
How does it work
The process follows along with the overview provided in other pages on here. To recap:
- Flash an application software to your ECU that allows for modified blocks
- Edit the calibration
- Flash the modified calibration
- Log the modifications and see what changed
- Logging with ED based ASW can be done by using the python based logger available here [SimosHighSpeedLogger]
In the case of open source tuning we really need to rely on two things:
- The ability to flash files to the ECU
- Using some commercially provided solution
- Using some open source solution like @bri3d's [VW_FLASH]
- The ability to edit the calibration
- Using software like RomRaider or TunerPro AND
- definitions files for the calibration (which point to where tables/maps/values are located in the raw bin) [Simos Definitions]
Definitions by and large are built by other enthusiasts that have taken the time to locate the maps. There are *factory* definitions files (called A2L) that provide everything, but those will only be used with other commercial software. They're also not openly available.
Why should I open source tune?
Nobody can tell you why you should or shouldn't.... but in general:
- You'll learn more about your car/engine and how things work
- You'll feel better about the changes that you've made because you can learn how to optimize them
- You won't have anybody to point a finger at when something breaks
- You can make the community better by learning and sharing
What are the risks?
Total ECU brick and or broken hardware. Nobody guarantees anything.
How can I contribute
If you want to help contribute to the open source project, start by getting acquainted with the process. Check out the github repos for the flasher tool and the definitions. And reach out to firstname.lastname@example.org
Thats cool - but how
Using Brian Ledbetters VW_FLASH Tool
- Build your tune(cal) in tunerpro
- Copy the cal to your raspberry pi
- Checksum the cal
- Encrypt and compress the cal to prepare it for flashing
- Flash it
Directions below will assume you have a directory on your pi for the flash tool (/home/pi/VW_Flash) and for your tunes (/home/pi/flashfiles/tunes)
Copy the cal to your raspberry pi
A suggestion is to create a directory on your pi (within your home directory) that can hold all your tunes. Something like /home/pi/flashfiles/tunes
Using something like winscp (or scp if you're on a mac, or any number of other methods to transfer files to your pi), transfer your tune file to this directory:
pscp C:\somedirectory\thisismytune.bin email@example.com:/home/pi/flashfiles/tunes/thisismytune.bin
git clone https://github.com/bri3d/VW_Flash.git cd /home/pi/VW_Flash python3 -m pip install -r requirements.txt cd ~/VW_Flash/lzss make
Checksum the cal
We won't re-explain everything... Just know that your file needs to be checksummed
Assuming you put the cal in /home/pi/flashfiles/tunes/thisismytune.bin
cd /home/pi/VW_Flash python3 checksumsimos18.py -i /home/pi/flashfiles/tunes/thisismytune.bin -o /home/pi/flashfiles/tunes/thisismytune.bin.checksummed --block 5
The above commands will use the -i input file to create a -o output file that's been checksummed as a --block 5 (cal block) file.
Encrypt and compress the cal to prepare it for flashing
Thanks to Brian and David, we can then encrypt and prepare the CHECKSUMMED file for flashing by:
cd /home/pi/VW_Flash ./prepareblock.sh /home/pi/flashfiles/tunes/thisismytune.bin.checksummed 5
This is a bash script that will re-run the checksum checker and (if it's valid), compress the file using VW's keys, and then encrypt the file and append .flashable to it. You'll now have a few extra files in your /home/pi/flashfiles/tunes directory. A worked example:
pi@raspberrypi:~/VW_Flash $ ls -l /home/pi/flashfiles/tunes/ 18tsi_MPI_IS38hybrid_FlexTiming_3000rpmscav_1.9bar_500nm.bin 18tsi_MPI_IS38hybrid_FlexTiming_3000rpmscav_1.9bar_500nm.bin.checksummed 18tsi_MPI_IS38hybrid_FlexTiming_3000rpmscav_1.9bar_500nm.bin.checksummed.compressed 18tsi_MPI_IS38hybrid_FlexTiming_3000rpmscav_1.9bar_500nm.bin.checksummed.flashable
The .compressed file is an intermediate file that we don't really need anymore. And the original .bin file is identical to the .checksummed file (except that the checksum doesn't match). You can continue to build your tune off of EITHER the .bin or the .bin.checksummed file since next time you make revisions - the file will be re-checksummed anyway.
The fun part:
cd /home/pi/VW_Flash python3 flashsimos18.py --file /home/pi/flashfiles/tunes/thisismytune.bin.checksummed.flashable --block CAL
This command will use the "flashable" file to flash it to the "CAL" block on the ECU. You can also use --block by number.