I cant control timing advance that has been commanded

My current mods are: stock ls1 long block, 100% Stock fuel system, long tubes, exhaust, cold air kit, aftermarket camshaft 238/242 LSA 111+3, fast 90mm intake , 92mm TB.

I set my Main spark advance in high and low octane to 22 degrees and I also set my Idel spark advance in both drive and park in a range meant for idle. The problem I'm having is that when I fire the car up I get the commanded advance spark I commanded but then there's a transition that I can't figure out where the rpms settle down and then spark advance goes random. This is the first time I have seen something like this from the 10 cars I have tuned. Some direction would be appreciated. Also, ignore the AFR reading. My wideband was not working for some reason.


Thanks,
Roger

Attachment 64160

give this a try