If your boosting higher than stock, you need to close your spark plug gaps or it will break down. I use BKR7E gapped at 24 thou.
Also code out your EGT sensors Temporarily to test as there are a known cause for this problem when it starts overfueling.
I have the same plugs. Ill check the gaps, have to find my gap checker.. Pretty sure I gapped them all but I'll doubled check.
EGTS are coded out and unplugged, mine died about a year ago or so, I was still stock and burned em out with stage 1.