I've taken out my 6x9's in the rear so i have 2 good sized empty hole and im making 2 of these boxes and the ports would go just under the 6x9 holes.
So its 4.41 cubic ft after sub displacement. ports are two 5in. at 17.1in. long for 34hz. My box wasnt tall enough so i have to make the ports stick out about 3in. to give it enough room in the box to work well.
So any comments are welcome, think it will sound good? and each box will have a 15in l7