a 6 cube box? is that with the seats folded down? i have a 2.0 cubed idmax in mine and it takes up a good half of the trunk already. it gets damn loud when i turn the volume up high.. but my front stage cant keep up with it so i dont find myself even turning it up that high.. speaking of high, i'm hitting a bowl of chronic. with about 900watts going to the idmax at volume