Timing was off by 20 degrees, dealer reset it. recovered some power loss but still not the full power that I had before
Few days later the car started misfiring and turned out to be destroyed fuel injector in cyl 2. I already replaced cyl 1 injector back in September shortly after the headgasket replacement.
Cyl 2 injector
Cyl 1 injector
Mechanic at dealer said because of grinding the head to fix the warpage, there's increased cylinder pressure from higher compression and causing higher temps which burns up the injectors. Not sure how much I believe him since the head was only ground 0.015mm, but I'll keep driving and see how it plays out.
Currently the car is doing OK at daily driving... Still not getting the full boost as seen here with before and after comparison of Vdyno
Car's throwing no codes, has occasional rough idle. LTFT is way into the negatives around -10 to -12 and STFT is always around +6 to +8, no idea what's going on. But I'm not happy with it.
Still deciding what to do next... Engine swap (may not fix whatever gremlin issue it's having) or buy the new 1.5T Civic (they come in 6 spd manual here and independent suspension would be nice).