So I have an issue. I have a 1986 pontiac firebird that I'm restoring. And based on all the measurements I have done. I have concluded that my trunk has a 12.7 cubic feet dip in the back and i'm trying to find a good pair of subs preferably 2 12's that can take full advantage of that kind of space and pound hard. I also want to make it a ported box as I listen to hip hop the most out of all the genres of music. All I want to do is make a flip up top piece that will cover the top of the dip to turn the dip in the trunk into a box itself. I think its called a free flow box? Any and all help would be greatly appreciated. thanks.

 

As far as subs are concerned; IMO Audiobahn, American Bass and Alpine R series are worth looking into. Audiobahn subs definitely have my vote when it comes into power, quality and price. Each type of sub will have its own parameters and box specs; some of the things that you will want to keep in mind is stuff like VAs L, Efficiency, Freq Response and Power Rating (in RMS).

VAs (L) or (Cu Ft) is the volume of air equal to the speakers spring characteristics in liters or cubic feet. This is a Thiele Small specification or parameter. Although you have approx 12 cubic feet of volume in that area, you may only be using 3-5 cubic feet for your speakers. Too small or too large of an enclosure (for your speaker) will make it sound bad and can actually hinder the performance of your system.

As far as efficiency, IMO the higher the number db, the better.

Power rating RMS vs Peak: I would much rather go after a higher RMS rating and not really worry about peak. A speaker's peak rating is a measure of how much wattage can go through it, in a very short amount of time (< a couple seconds) where as your RMS rating is a measure of how much wattage it can handle over continuous usage.

You can even find subwoofer box designers and calculators on the internet to help you with your actual design

http://audiobahn.com/

http://americanbassusa.com/

http://www.crutchfield.com/p_500SWR1...11#details-tab