Here is some info I got off ID's web site: (I have 2 IDQ D2 V2's)

Sealed
1.0cuft. 14Hz/40Hz
0.85cuft 16Hz/43Hz
0.55cuft 20Hz/50Hz

Ported
1.5cuft 28Hz 3"IDx13.75" 16Hz/28Hz
1.25cuft 30Hz 3"IDx14.375" 18Hz/32Hz
1.0cuft 32Hz 3"IDx15.5" 20Hz/38Hz