Quote Originally Posted by BIG WORM
couldn't you get the same effect by putting window screen and a rubber band on the end of the pipe? panty hose? an old sock? My friend had one in his front bumper, but it was more for looks, I thought. Isn't a open pipe the same?
no the straight edge of the end of the pipe will actually make less power than the same intake with a filter.

the velocity stack is designed with a radius curve in place to smooth the transition of the airflow into the pipe while improving velocity in most cases