I just installed a 2.5" magnaflow x pipe twin muffler system on my firebird 400. The mufflers are 14" I believe. Idle is quiet and low, muffled sound with out the chamber muffler hollow or high pitch sound. At cruise it is quieter as well and thank god no mind numbing drone like the flow master thunder america muffler. It is far from quiet during hard acceleration, maybe even louder than flow master exhaust. It comes down to personal preference, but for me, the drone had to go.
|