Something In my #5 Cylinder?

A piston manufacturer doesn’t matter as much or forged or hypers, if the ring gaps butted together. Butting them up on boost is a common issue around the forums.

I’m glad you run water/meth, what ratio?

In my opinion, your timing was way too high at 27. That’s less than 1 degree of timing per psi of map. If you experienced detonation, you may have damaged it then. Detonation is a wild animal under boost.
30% Methanol 70% distilled water. Yes, I know now that 27 was too much. I obviously didn't know that then... this will be an expensive learning process. This is my first time dealing with boost.