I'm going from flat wall to 4th. Running 6 zv5 18s on 6 synergy 7ks..my resonating freq of my van is 47 I believe..I'm doing 160 now on 4 zv5 18s and 2 synergy 7ks.my goal is 163/164 any design info would help..I also want lows around 28/33 ish..if possible..