Stock exhaust, what is this?

my aftermarket fmf muffler also has a "turbine" in it but it is open alot more than that, i dont see anything wrong with it, sometimes on idle you can see the smoke swirling and smoke rings shoot out once in awhile.
 
After my buddy stood the Blaster on the back end today in the woods, my FMF silencer fell apart. I'll be doing some straight-through-ish stuff on it whenever I go ahead and tear it apart.
 
Well I didn't have time to remove it at the weekend but I'll post here as soon as I've done it.