$550 Parting it out, had this on for a year with my Eisenmann muffler, decided to cut off the muffler one day for a real muffler delete, and wanted to have a loud set up for a while before putting back my full Eisenmann set up back on.
It's custom made by Detail Addict, 2 2.5in pipe from where you bolt on the header flanges, y-pipe with v-clamp to a 3in pipe up to where you weld ANY muffler you want. This straight-pipe is loud on its own. If you want just weld another straight pipe and add tips. Add your own muffler it'll still be loud enough. "Backpressure loss" I barely feel any. Ran it with a stock intake, run it with an aftermarket cone intake, it'll get louder no doubt. Drone with no muffler, no drone with a muffler (unless it's straight flow). NorCal folks only, depending on the day I could drop it off to you or meet up. If shipped the bill is on you but I'll get it shipped through a vendor and packaged nicely.
Video 4/27/13, just ask which minute/seconds were at what RPM's.
Here's an old thread for pictures and set up with a muffler.
http://www.e90post.com/forums/showthread.php?t=694465
http://www.e90post.com/forums/showthread.php?t=661826