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

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

Also bracing won't be .2

Id put that to .05

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...