I have the same system,,, the big difference is I made headers and downpipes Headers 2.0 off engine to 2.5 header 2.5 each side, to a single 3" pipe to the muffler. I get no bubbling ,,i just get a nice LOUD (except at idle) exhaust. go to New IAT reading for exhaust sound ,u will need head set at the end of the video is the exhaust sound. jim