Originally Posted by
2xLS1
HPT used to have a downloadable demo version of their software. Not sure if they still do. It would open a 99 Vette A4 file someone provided you. I don't believe you can access the tune repository without buying the product and registering. HPT will be able to scale the gear change. P1870 is almost always a bad TCC clutch and requires TC replacement. There are min and max PWM lock up tables in the calibration but I've never seen changing them fix a P1870 once it starts setting. YMMV