check RF to see if they have a chart for boxes on specific subs and specs on the subs whats the lowest ohm stable. the inside box volume could be different for a sealed and ported for those subs, if no info online then call RF customer support. theres a few places online that can calculate the box volume by the dimensions and thickness, i would recommend 3/4" mdf atleast.
im pushing 2 12s and compete with 15s hitting the same DBs and have a better bass response then a 15
im pushing 2 12s and compete with 15s hitting the same DBs and have a better bass response then a 15