I NEED HELP!!!!!!!!!!!

[AUDIO_BASSICS 0]

I have a 1994 chevy suburban that i am gonna take out the third row seat looking at doing 4 of the killer 18" subs but i did my box work and came up with @ 14 cubes for 2 18" tuned to like 25hz the curve looks killer but i dont know how to add in the cabin gain... so i need help thanks guys i am trying to get this done for USACI FINALS since they are having them in my town this year

[vladd 26]

build it try it then build another setup and try that. about the only way to figure out what'll work best for you, especially if you plan on competing at finals.