Ive read quite a few different posts on the net and there seems to be an argument with what the correct port area for one of these subs is. Im trying to come up with a new box and im unsure on what kind of port area i need. Ive seen on the smd forums someone said the minimum should be 52 sqin of port, then ive seen the number 38 sqin on other, and also had someone say they contacted sundown and it should be 20 sqin?? This is the only thing keeping me from starting on a new box. Can someone please help me out with this?

If it helps, box will be around 2cubes at 30hz ran with a hifonics brz2100. I know its not the best of amps but it is what im stuck with for now.

Also this may help some. sub has 30mm xmax at 70%BL

I know theres a rule of thumb with port area but im reading that with a sub with this much throw it requires more.

http://www.carstereo.com/help/Articles.cfm?id=31

Thanks, the calculator fixed my confusion. I didnt realize the area changes due to different tuning. My stupid mistake.

here's a calculator that calculates the port air speed. 
http://www.bitpusher.in/?p=portarea

Have no idea about that lol. I dont know to much about things like that

Have no idea about that lol. I dont know to much about things like that

 

you just plug in the number and see what port area is required to hit a certain port air speed. if its too high you get cuffing. 

ahhhhh ok. thanks for help man