[a1161979]

Due to the effects of cabin gain sealed subs often end up being very flat in cars even with box F3's of up arround 40Hz but ported is much louder and in your face so to speak

By the sounds of your needs and without T/S specs i would recomend about 100L sealed with the sub facing back or forwards, that is 3.5cf, sorry about the late reply and keep us informed on the build