24x timing question

[z28rob18]

Went to the track Friday night to run the car a little harder last time the best was a 7.75 at 95 mph with a 1.9 60' in the 1/8th. That was leaving at 3k rpm and shifting at 5500. This time I went and was leaving at 6000rpm shifting at 6500. The car went a 1.6 60' but the best pass was 7.93@ 84mph I only made three passes cause after 5500 rpm the car hits a wall and quits pulling I realized in the datalog that the timing at 5500rpm went from 32* to 15* no knock reading AFR was the only change I saw it was at 11.6ish till 5500 it went to 12.2. Any ideas what the cause is? I'm sure this is terrible for the motor I'm probably going to take it to someone before I hurt it but wanted to see if there is any kind of factory limits set on an 02 PCM