Can someone help me out on a box design for my 15"DD sub....I have a 2000 Ford Focus and want it to hit harder. I hit a 149.5 at the comp but in the box I hit like a 159.7 any help would be great.

Thanks
Shawn

 

add ports facing into the airsteram of the sub like those new jl boxes. the wedge or somthing they call it but its kind of hard to descride buti could try to draw it on here with text lol
port\/
......sub\/
..........port\/
___\ \_/-\_//___
idn how this sounds but my next box is going to incorperate this design

but bigger of course lol...