Greetings,
I have a 95 LT1 that is has a custom tune (S trim supercharger, cam, head work) and has a 4L60E behind it. The trans is stock and I dont think it is going to live, so I am going to change to a T56. I have tunercats so I can reflash my PCM to the T56 program, but how do I transfer the custom changes made for the engine? Is there a way to compare tables to see what was done? I want to make sure I do not lose anything, would it be easier or even possible to modify the current code to lose the automatic and switch to a manual transmission?
Thanks for any help!

 

they make a cable u can connect a 9volt batt to your cig lighter

 

The goal here is to keep my custom engine tune but switch to a M6 program, which seems to be the way to go unless it is possible to modify the A4 program to work correctly with the M6. I am concerned about the revese lockout working and specific M6 engine items to work as factory. Anyone know if tunercat has a compare function or a way to see what was changed on the custom A4 tune? I can download the custom A4 tune to my laptop and look at it, then would like to modify a M6 stock tune with my engine tuning changes before uploading it to the PCM. Problem is I do not know what all was changed for the custom tune. Could be many changes but a compare function would help find them.

 

Tunercat does have a compare function. Under files open your file, then under files select compare to. Select the file you want to compare. Open any table. Then under options select compare. Any values that are the same in both files, in that table, will be equal to zero. If a value is not zero then that value is different between the two files. The help file in Tunercats tells you how to do it. It also shows how to import the values from one file to another.

As far as I know you do need to use a m6 file with a T56. An auto file won't work the same. Some pin outs on the PCM, such as the reverse lockout, use the same pin but have different functions, depending on whether you are using an auto or m6 file.

 

Excellent information, thank you for helping! Plan will be to get the M6 bin and modify from there. I should have the M6 harness on the shelf so no need for repinning.

 

You don't need to keep the PCM powered to save the tune (although that's not the question he asked). The program is stored in non-volatile memory. The only thing you lose when you pull the power is the "learned" info, which is basically the long term fuel trims, and any stored codes.

 

You can change a few settings and make it an A4 or M6 file where it will work correctly. Going from M6 to A4, you have to be a little more careful because of all the tables you never used before bettter be set up correctly for your application, but from A4 to M6 is a piece of cake - you are eliminating half the program.

And you don't need to repin or change the harness at the PCM, rather you need to graft the two pigtails for the manual trans onto the proper wires in the tranny harness, and then get the switches on the pedals situated for the M6 setup.