DD 9512i box/port

[Cc2cuz]

Hey guys, I finally gotten to the point where I need to start building my box and just wanted to get some ideas as far as box and port size for the amount of power I'm running to my DD 9512i I'm gonna be pushing it with my DD M3B, (already installed) This is for daily only, no comps. Going in my 11 F-350. Don't have a whole lot of space, I've read about guys running 2.5 cu ft, but most of them are only putting around 2k rms to the sub. Should my box be smaller since my amp is larger and will be pushing more power to it??? Thanks for your help.