Can anyone comment if the 6.4 392 sounds better than the 6.1?
You can definitely faintly hear (and feel) the transition from 8 to 4. I also noticed the slight drone in 4 cyl mode.It's definitely not louder than the aftermarket exhaust setups. The automatic version is slightly louder than the 6.1L auto.
Pretty much, the 392 exhaust system is a clamp on system from the cats back. It has a X/H ish pipe immediately after the midpipes and then transitions to the big mufflers on the rear like the 6.1L has. The thing that got eliminated was the suitcase resonator and is instead replaced by two seperate resonators for each pipe.
On the 392 auto, you can slightly hear when it goes into 8-4 cylinder mod. As my girl stated, it sounds like the engine is burping and just sounds weird, however, it is hardly noticeable when driving it and you can barely hear the transition difference unless you are really listening for it.