No muffler on it. Just a big 5+" cat at the front. It does a lot of popping a crackling! The only difference between me and the rice burners is I have the HP to back up that sound....LOL! I dusted a WRX and an older Vette (00,01..) the other morning on the way to work that were messing with me! :lol: It's gotta really suck being beat by a 4cyl at 6:30 in the in the monring!
The whistling noise is an aftermarket waste-gate. Or so I was told. I've yet to really look for it. I will....it's always my mission to know my car backward and forward.