2 18" Kicker Comps

So I just picked up 2 18" Kicker Comp C18a's yesterday.
I was wondering if I can get some box ideas from you guys. I want it to be loud and tuned low.

How much space you have?

Well I have 48" wide by 40" deep by 17" high

You have enough space to build for them, but do you really want to? Why did you get those subs and how much did you pay for them? If it was me I would sell them as quick as possible and get better subs. Looking at the specs for them, you have a 110oz mag with a 3" coil and 500 watts rms. The only recommended enclosure is about 4 cubes each sealed. You could probably go 5-6 cubes ported but I would not spend money on a big custom box for these woofers.

I got them in a trade for 3 cheap 15's and I'm using cheap particle board haha

I would try 10 cubes common chamber sub up port back, with the port firing low toward the rear hatch. I'm assuming with the space you gave this is in a large suv. Tune it to 30hz and feed it 1500 rms. I would draw you up something in google sketch but I still suck at it. I'm hoping you mean MDF when you say particle board. It's even more of a waste of time if you are using that crappy press board stuff. It will fall apart on ya.

Well no I didn't mean MDF and this is not like a big critical build it's just something to get me by until I get what I really want. With my last box I used particle board for 3 15's tuned to 38hz and put some dowell bracing in there and hit a 141.3 with an 1100.2 crunch amp running maybe 400 Rms to all 3 put together.

First time using Google Sketchup but this is what it is going to look like but probably better haha.

Needs more port, general rule of thumb is do to 14-16 square inches of port per cube of box. So if your box is 10 cubes, and u wanna do 15sq inches per cube you want 150 sq inches of port. To calculate port area its just length x width, the depth of the port is your tuning. So to get 150sq inches of port on a 10 cube box your port would be 10x15 or 6x25 etc...

so how exactly do i tune the box like say tune it to 30hz like RRR37 suggusted?

Well, they have calculators online that will tell you how long to make your port after you put in your dimensions. But the longer you make your port the less cubic ft your box will be so you have to add that into your design. You will also have to add for subwoofer displacement and also bracing if you plan to do that