I came up with this design for my subs, but I am having trouble figuring out what size the enclosure will be since it's an odd shape. Just wondering how much space each sub will have with these dimensions.

since you are in sketchup, right click on the end and hit entity info

take the area and multiply it by 144 to get square inches.

then multiply by the length to get cubic inches.

then divide by 1728 to get cubic feet.

you will want to draw out your sides with the proper thicknesses to get an accurate estimate. for example, this enclosure i built recently. the volume was calculated using the area shaded in blue

So if my math is right, it would be just under 2.7 cu ft with 3/4" mdf, does that sound right?

are those internal or external measurements?

External

i have 2.631186 with that shape, and a width of 15, so if that is external you would subtract sides(unless its 16.5 wide) giving you 13.5 internal width, and a net volume of 2.368068cuft, before any displacements.

Cool, thanks. My subs call for about 2 cu ft sealed so that should work right? They are 12's so I figure after speaker displacement it should be pretty close. And I know in a ported box it's important to make the airflow as smooth and unrestricted as possible, but this being sealed the shape of the box should be fine too right?

It would be fine sealed. Volume is all that matters.

Neat, thanks for all the help everyone.