Trying my hand at designing a box for a Dayton Audio 18" woofer for my girls car. Its sub up, port up. But my question is, when doing a slot port at one end of the box, what do i put for the # of common port walls? If im thinking right, it would be 2 being that the port bends. Also it is 6.09 cuft @ 34 hz w/ 17.5 inches of port per cube. She wants it to go low, and so far that is the best port config. i have found. What do you guys think?