Custom Tune on 383 Stroker- Which XDF???

[CMB]

I have an AFI conversion kit for my 383 stroker. The kit came with a GM 1227730 ECM with a custom program for the motor. My problem is I don't know how to select the proper XDF for the program. Since it's a 1227730 ECM and V8 do I automatically select a $8D mask or do I need to do something more involved to determine which mask to use?

[robertisaar]

i would be very surprised if that weren't an 8D calibration.

take a look at the BIN in a hex editor(you can call up the one built into tunerpro by pressing Ctrl + H when the BIN is loaded), click over to position 0008, see what value is listed. I'm expecting 8D or possibly AA. if 8D, you have your answer, if AA, some further digging will be necessary to determine the mask. may get lucky and if the calibrator didn't change the PROM ID bytes, look that up and see exactly what calibration it started as.

[CMB]

Hi Robert. I opened up the bin as you suggested and at 00000008 it shows an 8D so it sounds like that's what xdf file to use. Thank you very much for the help.

For future reference, is the xdf file always shown at this location in the bin file?

Chuck

[robertisaar]

most P4 applications(8/16/32KB BINs), yes. there are exceptions though.

with the C3 applications, those varied a bit, but usually at 0004(I think).

with the P6/P66 applications, anything goes. some don't even have mask IDs.