stock pipe gutting

[Jgrimm400ex]

I was reading the forums about 10 pages back and i saw that someone said that you can gutt the stock pipe to get mid to top end and still keep the noise leval down and the spark arrestor.
PLEAZ HELP

[AtvMxRider]

I took the spark arrestor out and drilled a 1 1/8 hole in the back of the muffler and cut the screen off the spark arrestor and put it back in. It helped but it makes it louder.

[tprender]

You have to cut the thing open and take out the baffles inside. The inside is kind of like a maze to stop the air flow. Aftermarket exhaust are straigh though.