Well after going through 2 SLP Dual Dual mufflers I found a new Corsa muffler and had it installed today! Man what a difference in sound! The SLP DD was a tad quiet outside the car and seemed to start resonating inside at certain rpms. It also seems they are not made for more HP than stock as I am always finding the ceramic packing material coating the inside of my CME tips. I felt like I needed a dryer lint trap.

Corsa! - Wonderful deep sound at idle, mine seems deeper than other's i've heard due to the CME tip configuration. Very quiet inside at idle and at anything below 2500rpms, any rpm above and she starts to roar with a very distinct sound i've never heard an LS1 make before. Very little rasp with the ORY setup around 2400-2800 rpms but that is the nature of the beast with no cats on an LS1. 70-75mph highway crusing provides no resonance or drone which is exactly what I wanted. All in all I am very happy with the sound and tone. :worship:

Now as long as the muffler doesn't fall apart and start rattling I am set! With the QTEC closed it also seemed as if I picked up a little SOTP power over the DD also!