OK guys my friend just got 2 15 W3v2s in a ported boxed tuned to 38 or 39 hz. Its faces up on the trunk in a sebring. It gets very loud but it doesn't get low enough for me. Now Im pretty sure I'am getting 2 12" RL-Ps on a Cadence A7000 rated at 1500 @1 ohm. What kind of box would you recomend for what I want. I listen to mostly rap and I drive a Civic.

Any help would be great. I want to get a boxed designed before I order the subs