Sundown sub help and box design!

[scottthurlow]

I am currently in the process of a new build in my lupo gti. My external dimensions I can work with are

8" high

34" wide

15" depth at bottom

13.5" depth at top

Internally gives me 1.8 ft3 using 12mm birch to build.

What I unsure off Is the sub setup

I can decide between 2 sundown sa8 v2 in ported box tuned to 30hz. The box would be 1.5 ft3 for this to keep it square for ease of build using 18mm mdf. Port size is 0.83 inch x 12.03 inch and about 27inches long.

Could someone think of a better port option with the space I have

Or

3 sundown sa10's in a sealed box using 12mm birch with a 1.8ft3 box

What would the difference in spl readings be etc and would there be huge different in loudness between the too designs?

Any help etc would be great