I have 2 SSa Evil 15s with 4 Stiff Spiders on 2 Crescendo BC5500s in a Hyundai Accent Hatchback

 

Will this 4th Order Wall Design Work?

 

Sealed chamber 3.25 Cubic Feet After Displacement

Ported Chamber 6.25 Cubic Feet After Displacement

 

Port 6"wx14"Hx10.25"D Tuned to 45hz (84 Cubic Inch Port Area)

 

Thank you in advance

 

 

How did you pick your volumes and tuning? 

 

If you didn't model, you need to go back and do that first.  That is the only objective way to predict how it will "work"...

95 Honda

Box builders in my area gave recomendations of 1.3cf to 1.6cf per sub for sealed section then 2:1 ratio for ported section of sub. then 12-15ci per cf for port area

Then the box builders in your area aren't anyone you should listen to.  I'll give you hint, anyone who says use a ratio has no place in ever recommending anything.  The "per cf" is also incorrect.  Based on 2 out of 3 being wrong, I'd bet $$ that the size recommendation is as well.  It is all very easy to check in WinISD though.

 

Btw, you are also using the term 4th order incorrectly.  A standard ported box is a 4th order, a bandpass box can also be a 4th order.  You should really specify.  All that being said, it is also likely that for your goals a standard 4th order ported (ie, non bandpass) box would do better.  Of course we don't know your goals so that is hard to say, but there are very few things a 4th order BP does better than a simple ported enclosure.

The current box now is 10.13 cf after all displacement the port is 4.5"w x 9.25"h x 9.5"d

 

I know the port is too small. Can you give me specs to make propper port?

Or can you help design a bandbass? the amount of space i have to use in the vehicle is 

 

38" wide x 28" high x 21" deep

Why bandpass?  That isn't logical...yet.

The Evil isn't really ideal for 4th order bandpass.  While I'm sure it's not a definitive measurement the qts on the Evil isn't in the range which benefits most from a 4th.  I'd stick with the 10 cubes you have and go ported.  if you double up the top and bottom that gives 25 inches of internal height.  So 25 inches tall and 4 inches wide would work.  Even 5 inches wide would be good although with that much power and that size box I'd keep the sq in per cube on the lower side.  Tuning will be up to you but it's gonna be stupid loud no matter what so I'd go low end.  28/30 or so.

Do you have pictures of the current install? Are you not getting the output you expected or something?. Whats your electrical like?