Timing drifting at higher rpm

I have been helping a guy tune a Fiero that has a 3.1 with an upgraded camshaft and has been turboed. It is running the code 59 software and has been converted to a newer ecm and DIS. We were checking the timing a light the other day and the F1 table said the timing was at 21 degrees and the crank timing with the light said 15. I moved the spark reference angle from 69 degrees down to 63 which lined up the marks with the map. I then set the map to 18 but had to set the spark reference angle to 66 to get the crank to move. When you speed the engine up say to 2000 rpm where it is set to 26 degrees on the F1 map I'm seeing 24 degrees on the crank. Does the HI RPM Advance slope have anything to do with dialing this in? The Hi RPM Advance slope is currently set to 1.98 degrees/ 1000 rpm.

He also said the timing on the engine would not change at all when reading the balancer when he first checked it. I turned on the ESC under Options 3 in the Flags section but I'm not sure this changed anything or how he was speeding the engine up by hand when checking with a light or just changing the F1 map with the keyboard.

Thanks for any help.