Well there is two things going on in this thread, one is the talk of the ideal sound for our six and the other, the best flow using a certain exhaust setup.
Sure a person may lose hp potential with the flowmasters but they will still gain over stock, this approach, is geared more towards achieving a specific sound, due to the use of internal baffles vs packing / pipe with holes in it, as far as I know, only a flowmaster could provide this.
You may be suprised, glasspacks are a little more restrictive than you might think, due to the louvers inside.
There is science to the X pipe, its not restrictive as one might think, your only joining a small area of the pipe(s). Do a search on your favorite search engine, you should find more hp gains using an exhaust system with an X pipe, over running open headers. From what I understand the X pipe not only equalizes the engines exhaust pulses but it tricks the system into thinking the ehaust system is larger. Kinda like subwoofers. You take a small box and fill it with fiberfill, it will have a deeper tone, the frequencies slow down, in effect making it appear as if the box were larger. Filling a box and making the box appear larger makes no sense to me, but it works.
What truck did you put the exhaust on, what engine you using? Post a soundclip, always interested in inline sounds.
