Okay so i have 2 sa 12s on the way and a brz1700amp, i am trying to design a box for my audi a4 that will be sealed off from the trunk into the cabin, i have never done this before and i am still learning about box rise, to combat box rise i would like to do an 8 inch areo port, as well as 45s and fiber resin. the space i have to work with is 35" wide, 17" tall, and 20 inches deep. i am aiming for about 4.2 cubic feet ( is that enough?) and around 35hz tuning. i just need a kick in the right direction!