Tuning for 4G TL is now a possibility with KTuner. KTuner is a tuning software with a customizable interface and tabbed layout. Items such as gauges, tables, and graphs can be added to tabs and moved into position just how you like it.
KTuner for the 4G TL is currently in BETA and new features will be added as they are developed. Currently all the important tuning feature are available such as, Rev limits, Ignition, fueling and knock. In addition to being able to make those adjustments real-time logging, recording, playback, and graphing are standard items available with the end user version.
Part numbers for usable ECUs include:
37820-RK2-A01 through A13
37820-RK1-A51 through A78
37820-RK2-A71 through A96