I've had 3 customers show up for a tune now with psi conversions ecu, and every single one the trans tune has to be set super low ex. If I want to shift at 40 I have to tell it shift at 20.. also every single one the speedo was way off to the point of me thinking the vss is bad. Does anyone know what the TCM uses to calculate speed because obviously it's not the normal speedo calibration. Also gear / tire wizard does not make it correct.