I run JBA headers, no cats, and 40 series flowmasters. I dont have any sound clips but it just sounds kind of choppy when it goes into 4cyl. Its not like it sounds like a 4 banger or anything, still sounds like a v8. Sounds good to me.has anybody put a muffler on the nbs silverado's? and if so does it sound weird at all when it shuts down from the 8 cylinders to the 4? sound and vid clips welcome.