Hey Toan,
I'm new to this forum thing but, I just bought my 2013 GC 3.8 track. I purchased almost the same things you already have installed like: ARK down pipe, H pipe, and Catback exhaust. I also purchased from SFR and intake, pulleys, and Stage 1 ECU. BTW did you have any problems or complaints with these mods any help is greatly appreciated.