So quick question...

Had the car tuned Friday and it was finally nice out today with dry roads and bout 45 degrees so I went and played a bit... Ok a lot lol and did probably 15-20 full boost runs with many times using NLS... However 3 times I had a crazy noise with drop off in power. Once was from a 2-3 shift and twice from a 3-4 shift. It only happened over 6k rpm and ski des like a scratching screetching sound. I immediately let off and backed down a bit each time. Each time it happened though was after the car was shut off... Once it happened once it didn't do it again unless the car had been turned off. Also this only happens at WOT mid shift letting off clutch into next gear. It alllllmost acted like a miss fire??? Stock plugs but I'm only at 29k miles. Car has never been sea foamed to my knowledge. I checked the charge pipes and intake, all nice and tight. Info a out car and tune below:
2010 LNF hptuned
A/f always at 12.6-12.7 now
20 psi boost
6.5k redline in all gears
K&N SRI
Aftermarket upper CP
Everything else on car stock

My thoughts were maybe plugs? Seafoam? Bpv on the fritz? I just don't know but I don't want to hurt anything...

Any help appreciated! I guess this post wasn't that short lol let me know if you need more info.

Thanks guys

 

Anyone?