Ok so I'm going from a 2.73 in my '95 A4 to a 3.42 from an M6. Should I rescale a virgin 2.73 file or start with an M6 3.42 file and switch it to auto?

I used to hear from time to time that you really shouldn't rescale the rearend ratio b/c of rounding errors, etc within LT1 Edit.

 

I used tunercat so I don't know what LT1edit has. I used the speedometer tool in tunercat to change to a 3.42 ratio from a 2.73 on a 94. I just used my existing bin file. I don't think you can use a m6 file and convert it to auto. I think there are things in the files that are unique to auto or m6 that can't be changed.

 

Use the A4 file and type in the new ratio. Since the tone wheels are different on A4 and M6 the speedo will be way off if you use the M6 program. Also, you need the A4 file to control all the shift solenoids and torque convertor lock-up which the M6 file will not have.

 

Heck I thought both files were the same and when you checked the M6 box it just stopped looking for auto-type input signals.