ok you are looking at around 6.5 cuft after port and sub displacement.
for you to have around 120sq inch of port (6 x 20)tuned to the frequency you want, the port would be around 31 inches. that means you have to bend it cause your depth is only 27 inches.
what you can do is reduce the port area to 84 sq inches (6 x 14) and have a length of 21 inch so it will work.
you can also make it an interchangeable so you can tune it higher.
if you can raise the height a bit more it would help alot. don't you have a suv? you should be able to put a higher box in there. your mounting depth is 8 inches so if you have a port that is 6 inches tall, it barely clears it.
this is my friends box, its going in a 92 dodge daytona (hatchback FTW), im almost positive the box can go up to 18" tall. i was just being precautious for the back window. depth and width are max.
