To use this script, copy the LapTimer file to your computer, and determine your correction factor. You can find the correction factor by logging both GPS and OBD speeds at a steady speed. Then figure your correction factor by dividing GPS_SPEED/OBD_SPEED. Your GPS speed will typically be lower than your OBD speed.
Once you have the file and know your correction factor, run the script with the following options:
python hlt-speed-tweak -i [LapTimer file location] -c [Correction factor in format .95 or 1.1] -o [Optional output file location, default is "corrected_obd_speed.hlptrz"]