Box HElp

[weeznur32 0]

So i built a box and everything was lookign good. I ordered two 3" port tubes. I tried to put the box in my car without the face board on and it fit. However with the front board on it did not. I had to therefore inset the board changing the demensions of the box a bit. The box demensions are now 25.5 X 17 X 16.75. How long do my 3 inch port tubes need to be to achieve a tuning of 33hz. The woofer i have is the 15Q so displacement is .19 cubic feet. Thanks for the help.