Ok, I am going to have a box made for the IDQ12 D2 V2. I measured the space in my trunk to see what I could fit, here are the parameters I came up with to get 1 cu.ft total that the sub requires.

16"W x 13"H x 12" D = External Volume at 3/4 MDF

Total internal volume is 1.03

Mounting diameter = 11"
Mounting depth = 5.75"

But the speaker displacement is .07, which would turn the cubic feet to .96 inside the box.

.96 cu. ft really worth altering to make sure the box is exactly 1.0 cu. ft?

 

Actually I figured out how to get closer to 1.0 cu. ft.

15"W x 15" H x 11.5D = Internal Volume 1.05469 cu. ft.

1.05469 -.07 speaker displacement = 0.98 cu. ft.

I also don't know what size bit should be used to pre-drill the holes, what size is best?

 

if possible, i would bump up the cubic footage to around 1.2 cubic feet after displacements

 

Yeah, pretty sure I can do that by adding some to the depth.