Do you think a 210/218 47* .551/.551 112lsa is big enough to account for the noise?

 

My truck got louder with the 214/216 in the 5.3 and it is even louder than that now with the 5.7 and 228 cam. The 6.0 are more prone to droan as well.

 

This is what I've heard as well. I remember reading about how exhaust manufacturers were have numerous problems building catbacks for the 6.0L, as it was very difficult to tune out the drone, resonance, and overall noise.

 

The 6.0 is very loud and does drone alot. A big Magnaflow will not tame it. If you want it quiet you might want to consider a HD Big Oval series Flo Pro Muffler. I have heard that they do a good job of keeping a 6.0 quiet.

 

Two Magnaflows in series might though.

 

Got Pacesetters on the way. I was thinking about running duals with an X pipe and two Magnaflows (one on each pipe, not inline) and having a dual exit on the pass side behind the tire. Keeping the cats but might go high flow to replace stock ones.

Think that would quiet it down?
Lose bottom end TQ?

 

Instead of the x-pipe you could get a Magnaflow 2-in, 2-out, which has a built-in x-pipe inside the muffler. Together with two more mufflers (one on each pipe), you'd probably be in business for quiet...and I doubt you'd lose any bottom end, might just gain some.

 

and lose some top end from the additional back pressure.

 

Kindly explain how you gain any backpressure from a straight-through exhaust.

 

I had to use use a large dual in/out magnaflow and a couple of glasspacks in-line to kill the drone of my old 6.0