Need to build a SPL box for 2 15" woofers

[cuchis]

hello guys

Im new in this forum, the thing is the I run in IASCA and DBdrag, and I need to get a good box to go in SPL, my car only do 155dbs but I now the I can get more dbs yet, I run in ultimate 1 class so meabe somebody can give me a hand.

thanks for all

cris

here is one pic