i found the program that i use 2 make my sub boxes, very informative and easy to get the right size and shape that will fit ya boot and still keep the right internal dimensions

its only about 2MB and very well worth it!

DLS Probox 2000 (http://www.audiophiles.com/program/dlsbox2000e.exe)

To design enclosures I use WinISD.

On the subject of helpful enclosure calculators, check out the bottom of this page (http://www.the12volt.com/caraudio/boxcalcs.asp). :)

I just used the one found on caraudioaustralia. seemed to do the job :p

i tried 4-5 different sub-box calculators, and i found that winISD is definately the best......and hell if FHRX uses it im sure its gotta be good. :P

I have found it's the most user friendly so far. Some are just way to complicated for any non-scientist to understand while others are just plain hopeless. WinISD seems to be the go. :)