’03 ram qc, cvr’s weak

okay heres the deal, 2 10" cvr's, kx450.2 amp, and a box off ebay....airspace is rated at like .68 per sub below the kicker recomened .80, basicaly these subs sound wimpy in this truck....now my question is, is there too little airspace, power or both?? testing things out i put the cvr's into my custom ported box in my truck, the box was built for comp 10's, and they actually hit decent in that box but still lacking imho compared to my plain comp10's that pound....obviously the difference is probably tuning but that fact is theres much greater airspace and they actually prefrom any recomendations would be appreciated besides bashing kicker im very pleased with my personal setup

build a ported bot to kickers specs, then put more power to them. I would put 500 per sub. I ran 1000 per sub to 4 15's for a while.