I am working on my plans for my box and would it be acceptable to cut a hole for a round port and have the port extrude from the box some distance? The Box is 3.5 cubes or so tuning to i hope 32 Hz for a 15. Could it be outside to get more airspace?

it will work but it looks really weird lol

If you have any of the port outside of the box it will add to the volume of the box changing the frequency, unless you compensate in your calculations for the increase in volume you will be off in your tuning.

but youll be louder.

If you have any of the port outside of the box it will add to the volume of the box changing the frequency, unless you compensate in your calculations for the increase in volume you will be off in your tuning.

Incorrect. You subtract the volume of the port from the volume of the box because your woofer doesn't use the space that the port takes up. In my case, my 2 12's see 3.5 cubes total, but the box is a hell of a lot bigger than 3.5 cubes because the port is really big. An external port is just an extended one, it lowers the tuning and doesn't affect box volume at all.

For example, you could take a 2.5 cubic foot sealed box and cut holes in it, add an exteral port to the hole you cut (the tube would be sticking out) and it would be 2.5 cubes tuned to whatever the port is tuned to. Spl guys do it all the time so they can change tuning whenever they need.