I am currently in a hunch. I want to create a box(ported) for my L5 15inch subwoofer. My trunk only allows certain dimensions, if someone could help me with a diagram and few dimensions for the proper cubic feet of air room needed I would appreciate it .
The top of my trunk to the bottom floor is 18 inches, left side to right side of trunk is safely 20 inches and the back of the trunk to the seats is safely 20 inches .