Hey all. I've been reading these forums for a long time, and thought I would contribute something back. I have developed a very basic program for tuning VE tables in your car, using nothing but a logfile containing RPM, MAP, AFR, and TPS. It is written entirely in C++, without a GUI at the moment (but hopefully once I get around to learning QT it may one day have one). It supports lambda as well as AFR, and also supports PE mode adjustment (though I have not been able to test it, so proceed with caution). This is designed to further the idea of free and open source tuning, as this, PCM Hammer, and the ability to log parameters (easily accomplished through an AFR gauge with OBDII capabilities) can provide an equivalent platform to HPTuners or EFILive, at least in theory. In reality, there's probably all sorts of issues with it - I'm a freshman computer science student that threw this together in his spare time so I could tune my own car. Please feel free to give it a shot, I gain nothing from this and just want to give back to all the people that have helped me over the years. Please let me know if you find any issues or bugs. The project can be found at https://github.com/hkaase/VETuner. I have written lots of documentation in the "wiki" section, and it should be enough to get you up and running.

 

Very cool.

The wiki pages state that it's biased to LS engines. I think it's a bit more restrictive than that ... I think it's biased to Gen 3 LS engines with an actual VE table, rather than a VVE table.

Where are you going to school? I got my EE from Gonzaga in '93, my senior project was software for a standalone EFI system. Nothing like getting college credit for working on your hobbies.

 

You're completely correct. Gen IV is alien to me, so that's a totally new concept. Enlighten me. I'm assuming it's a combination of DOD disabling cylinders and all the other stuff? I will have to look into adding this. I personally wouldn't be able to use it because PCM Hammer does not yet support gen IV stuff.

I'm currently attending Baylor. I'm actually considering doing something with EFI for my capstone. Maybe machine learning self-tuning capabilities?

 

Since GM added DOD, and other stuff, it would have taken too much room to store a VE table for each mode. So they store coefficients that get plugged into an N-dimensional equation that will produce the 3 dimensional VE surface required for each mode. Not sure if the equation is the same for each mode, and only the coefficients vary, or if both vary. But it's much less straightforward for the amateur tuner. HpTuners was kind enough to provide us with a 'VVE' table that we can modify, and then they back calculate the coefficients for us, which are what is actually stored as part of the calibration (tune). I believe that a guy going by 'Bluecat' on the HPTuners forums built standalone tools for this before HPTuners integrated the equivalent into their software.

In any case, it's much more complicated in Gen4+ controllers.

 

Wow, my brain is super conflicted here. I want to be impressed at the intricacy of the system, but it certainly sounds like a pain. Interesting, and something I may revisit in the future. In any case, a GUI is a higher priority. Most people I know run DOD deletes etc. anyway, and I only have Gen III. Thanks for the explanation.