i know everyone on here always says you cant tell but i just want a ballpark range. do you think i can hit 140db with 1 arsenal 12 ported at 35 hz in a 2.5 ^3ft. box? its running off about 850 watts. got a high output alternator with 0 gauge big 3. its in the trunk of a honda civic sedan. also, the rear fill speakers are out to port my trunk into the cabin. what else would you need to know to give you a better idea?