the box i have is 38 x 16.25 x 22 the port is 4.25 wide. i was thinking of getting two fi BL 12's. i currently have two alpine type r 12's. do you think this box will be big enough for the lack of space i have.

are those the internal dimensions? What is the port length? I'd say regardless, just from the dimensions you gave if those are external and you have a little over a foot displacement from the port you'll have enough. I'm getting you'll have about 5ft total, which is the max recommended. What freq is it tuned to?

i had my q15 on a port of 5.25 X 16.5 ... quite big... and I like it.

im not to sure on the port length but i have the website for it. its at subwoofertools.com

http://www.subwoofertools.com/forum/ported...mp;Fs=&CE=0

I realised that on your link that you put xmax of 18.2mm instead of 21mm and displacement of 0.71 instead of 0.15 cu^3 per sub which is 30 cu^3 for 2.

as for your current dimension of 38 X 16.25 X 22 maybe you can go with port of 5 wide X 14.75 tall X 28.5 lenght with port area of 75.75 and box volume of 5.47 cu^3.

Someone can confirm as I always get different measurement with other programs.

I realised that on your link that you put xmax of 18.2mm instead of 21mm and displacement of 0.71 instead of 0.15 cu^3 per sub which is 30 cu^3 for 2.

as for your current dimension of 38 X 16.25 X 22 maybe you can go with port of 5 wide X 14.75 tall X 28.5 lenght with port area of 75.75 and box volume of 5.47 cu^3.

Someone can confirm as I always get different measurement with other programs.

the reason its at 18.2 is because its a box for two type r 12's. and thats the biggest i can go in the back of the car. it takes up the whole hatch area. which is 38 by 16 and a quarter by 22.