Ok the hatch is 3' 1" at it's narrowest point, and just below the top of the back seat is 14". I want the box to slop off at a angle so that the subs will hit off the back glass. I want to keep SOME space in the hatch area, so I was only gonna make the box 16" thick. Each sub needs a min. air space of 1 cubic foot and the max. is 2 cubic feet per sub. I want a sealed box because I really don't have the room for a ported box and a bandpass is out of the question. Heres a link with the specs on the subs I want.
http://www.audiobahninc.com/prod/woofers/AWC12.htm
Or course these subs would ROCK, unfortunly I can't afford them(needless to say my ear drums are glad I'm poor
http://www.audiobahninc.com/prod/woofers/AWT12.htm