I've been tuning for many years and can't help but wonder if another platform is responsible for this because that's the only time I've seen something like this happen. I'm specifically aware that there are tables that LS1 edit provided access to that this platform does not. In this case, it was a Diablo hand-held that had been plugged into it before. What's happening here is that the calibration file is not referencing timing from the main spark table while driving, rather the Idle Spark Advance>In Drive table. I know this because of the values that I have in each table and when changing the ones in that table, it affects the result while nothing in the main spark table affects anything. I'm aware of the "Main Spark Table Select" values and left them stock as well as tried changing them to no avail. I'm not aware of anything in the file that will cause this. Anybody else ever experience this and discover what's going on? Maybe one of you guys experienced with hex editing these platforms? File attached for your review.