BL 12 box?

[ncc74656 2]

friend wants to buy a BL 12 and place it in his car. he wants it even with teh rear seats so its a bit tall of a box. does this look proper for such a sub?

 

http://imgur.com/a/IUDaJ

[EPerez 236]

I would do AT LEAST 35-40in2 of port area. Also he wants it tuned to 39hz? What music does he listen to?

[EPerez 236]

Also bracing won't be .2

Id put that to .05

[ncc74656 2]

he has heard my SP4 18 at 34hz and i sold him my old BL 18 at 44hz. he wants a balance between the two so i thought id halve the difference and see where it gets us. some buddies around me have said they prefer 39hz for listening so i figured its worth a try. i know that while i am very happy with my 34hz tune in the low end i am not happy with it as a daily driver.  i suggested that he may want to do a sealed box but he defiantly wants a port. 

 

with the .2 bracing i wanted to reduce the internal space so i was going to add wood until i got to that amount of displacement. he is putting it on a 1500W amp but the amp puts out far less power than my kicker so from a comparative pov i wanted to raise the cubic footage to allow for a more matched power handling build. im not sure if id want the box to be any further on the outside edge of specs. 

 

he wants a large box for this 12. the whole reason he is buying a 12 (wich is teh same price that i sold him my BL with box for) is that is mother wont let him use the 18" as its to big. i made the sale on craigs list and it allowed me to upgrade to an SP4 for rather cheap so it was a win/win for both of us but now he is kinda stuck...