in no way do i mean this to be spam but for a while now we have been working hard to bring everyone a site devoted to aftermarket car exhausts. Being an E46 M3 owner myself were starting with BMW and working our way around. Here is an example of some exhaust pages
Eisenmann E92 M3 Page
Supersprint E92 M3 Page
From their you can see information about the exhaust and all videos on the site from that exhaust. If you go back to the homepage of the site you can browse by exhaust manufacturer for now and later by your car model.
I would appreciate everyones input on the site and any ideas, it is a daunting task to get all the exhausts on the net but we are cracking away at it. Admins if you want more information to perhaps make a sticky for all the M3 exhausts let me know as well. You can upload your own vids to help the site grow as well and their are many many mods to come. its just a beta right now.
Regards, hope everyone fines it useful.