Car is 2012 scion xb, I got my subs in saturday, super fast shipping from obsidian. I got the car interior stripped today, going to build the floor starting tomorrow. I have more than enough room either way, and I had to lose the back seat either way. I was gonna do subs up, port back which was the loudest in my expedition but this is alot smaller car. If I do a wall, I have to do subs side by side with port across the top of box. The car is my daily driver, I drive at least 30-45 miles 1 way every day, this is reason I am considering subs up, port back or even subs and port up. I have driven a walled vehicle before for couple years, I just cant decide if I want that now. Any suggestions? Anybody done any work in scion xb. Subs will be in 5.5-5.75 cubes each tuned to 29hz