Couple questions about a box.

[etaks_crew]

Well I finally was able to find a new job and get some cash role going. I have built a few boxes before, only one being ported(I didn't design it). Here are my questions. If I build my box to where it gets bigger once I clear my wheel well would this affect my sound( kinda like a rectangle on a bigger rectangle to get the right amount of air space ). Also I like how my current box sounds verses others I have had this being the only subs up port back box. But this time I would like to try aero ports. I know when you use a slot port that you should try and have it as far away from the hatch as the port is wide. How does this law work with aero's? Like if I use one four inch should it be 4 inches away, If I use two 4 inches should it be eight or if I space them apart from each other could I still use 4 inches away?

Here are some examples.the red would be ports.

[etaks_crew]

Bumpity....

[kl0wn]

Building your box from the bottom, and then going out farther once you clear the wheel wells shouldn't really change that much of the sound, if it all, it'll just give you more air space. You could build like a floor to put between the wheel wells so it'll be the same all the way across, so you won't have to worry about adding angles onto the box, then that means you could be saving space to put amp(s) + battery(s) underneath that "floor". For the aero ports, not sure how to explain it, but let's say you have 2 4" aeros, like in your 3rd picture (2nd picture with ports) you would only have to keep it 4" away from the back hatch, not add the ports together to make 8" away, because they're 2 separate ports technically. Somebody please correct me if I am wrong about any of it.

[jizazz12]

as long as you measure your box accurately for internal volume then you should be fine,won't really know exactly what type of sound your going to get until it's built may have to play with the design a little.as far as aero ports go i love them rule of thumb on aero ports is you want it to be at least the diameter of the port for clearance for a four inch port you want to try and get at least four inch's from any internal structures walls other ports bracing extc. you also get a slight d.b. gain when using them.

[etaks_crew]

Thanks for the input on the aero's should I try and space them apart a little bit or can they be close?

Edit sorry read the second rely wrong.

[Decaf]

space them apart

[etaks_crew]

Also when figuring my tuning how do I subtract the displacement of the port. Just find the volume of the port and subtract it. When useing port calcs would I have to change my displacment after figuring the volume of the port?

[jizazz12]

if your going to use aero ports all you need to do is is figure out port displacement length x circumference and subtract it with the rest of your internal displacement sub's,bracing and what not. if you go to precision port .com they have a port calc to help you figure out your port length for tunning.

[etaks_crew]

Damn I feel really stupid right now but I've been doodling a couple box's. When I try and figure the port displacement, I would do pi x radius^2 x length( I think this is right) but that gets me it in inch's when I put it into feet I don't get much for displacement. I'm I doing this right?

So If I have a 6 in aero. I would do 3x3x3.14x lets say 12. I get 339ish and in feet I get .19 Does this seem right or am I doing this wrong?

Numbers I just picked out of the air nothing is finalized at all.