hello everyone so ive been back and forth on my setup I have a 2013 Honda fit so far ive taken out the secondary cat and gone straight 2 inc piping(and most all systems ive seen for **** ton of money are 50mm witch is slightly smaller then 2 inc anything bigger then 2 inc seem way to much for this weak engine ) back to the stock muffler its not loud really at all now besides for the little backfires here and there cause the stock muffler power wise should I remove stock muffler or keep it I have a custom straight pipe that would replace the muffler , keep in mind theres a huge primary cat in front of all this for backpressure so please people let me know whatca all think