External dimensions are 41"long x 18"high x 17" deep
The internal volume before displacement is 5.8 cubes

After Displacment of port and subs its 5.3 cubes
Material is .75"thick

I want it to be tuned to 30hz. I got the port demensions to be 4"h x 10"w x 14"l

If anybody is wondering the subs will be firing up with the port on the front. (Its in a hatchback)