If you remove the seat mat'l stuffing and put a sub there anyone who sits there will squish the cone unless you grill the front over the cone. If you dynomat the trunk an face it away from you it will pound louder I find. I have two 10" xtant pro series subs in a 1/2 MDF ported box. The volume is 4 cubic feet and two 3"x5" deep ports are in between the subs. I hit 146db running with a Kicker dx350 amp consistently. If you dyno mat the trunk and cut holes in each back seat and have subs visble it would be cool but not even close to loudness of a box. It is hard to seal the fold down seats.
