I have a 1999 Pontiac Montana minivan... It is no longer a family vehicle.. I have 2 12" kicker solo x subs.. They are powered by 2-Hifonics Brutus 2005D amps..The subs are currently in a 5 cu. ft/sub ported enclosure.. The subs came in this box when I bought them.. I took out the 3rd row seating and placed the subs facing the rear.. I took it to a U.S.A.C. competition and soon realized that I had some major problems.... My van roof flexes about an inch(from b- pillar all the way to the rear )when hitting the low freq. I want to wall out this van (right behind front seats) with speakers and port facing forward.. I would like to know what size box as well as port would be optimum for these two subs..and tuned to what frequency.. I think that if I wall this van out from where the flexing starts it should resolve a lot of the problems.. This will be for Pure SPL only... Any help would be appreciated.
