PSI 12" Building New Sub Box PLEASE HELP

[FosgateLife]

Okay so, im used to designing my own boxes and for what they are, they're OKAY. Im NOT a pro or anything but i can build a bad ass box, but i think i just have the design wrong. idk... So right now im running a Fi SSD 12" with a PSI Recone. 1000 rms but i plan on running it at around 1300-1500 daily soon. Just recently i heard an american bass XFL 12 in a REALLY NICE box with basically the same specs as mine. Only it blew my mind. i was speach less. ALOT louder, and ALOT deeper than what mine is hitting right now. And i want to change it. I know my sub has ALOT of potential i just want to build the proper box to get maximum output for my daily driver.

My box now is 2.3 cu ft, 45's on corners, bracing around sub hole area, 4 inch aeroport, tuned right at 32.5 hz.

The amount of space i have to work with might be causing the problem here im not sure. my dimensions im using right now and i want them to be the same) are 40 inches wide, 15" tall, 10" deep. (I can go up to 12 at the max)

I builyt a 4th order and didnt like the sound. Tried a T-Line but couldnt get the dimensions and tuning right, never tried a horn box but will be up for the challenge maybe? idk whatever seems best

So if someone could help me figure out the loudest daily driving box i can get will be.... Im going to seal it off from the trunk, facing in the cabin once i get it built. Just someone please help me? (: thanks in advance