a little box help

[rocky 59]

okay a ported box with the internal deminsions as- 38.5'' wide 12.5'' tall and 6.75'' deep.

and its an ava 12'' sub so im giving it .2^3ft displacement.

that makes around a 1.6^3ft box

and if i use an aero 4'' firing towards the side wall and its 13.5 long would that port it to 35 Hz?

[Skip01]

http://www.carstereo.com/help/Articles.cfm?id=31

I put in the numbers and it looks like its gotta be 14.35in.
But let someone else confirm it.I just plugged in numbers.

[rocky 59]

http://www.the12volt.com/caraudio/boxcalcs.asp
thats what i used

[bjfish11]

I got 15.35".
This is what I use.... http://psp-inc.com/

[rocky 59]

**** all this different lengths.

i need to know the right one lawl