The important parts?

[RAM_Designs 5,000+ posts]

I got around 7.28ft^3 before bracing displacement, but the tuning still seems right at 32hz. The port is too skinny though, you might have some noise issues depending on how much those subs can move.

 

[sackamous 10+ year member]

I missed something on the lenght of the wood in the port, I went back over the numbers and came up with 7.35 useing the exact displacement of the subs(went look it up). If I change the depth from 20 5/8 to 21.5 that ups the after displacement to 7.79 after takeing out everything. Should brake out just about right after a few braces, was thinking 1" rods?

 

[RAM_Designs 5,000+ posts]

Go with the widest dowels you can find, normally 1.5". It's also good to cut a larger diameter circle out of MDF to go at the end of the dowels so that there's a larger surface area bracing the wall.

 

[sackamous 10+ year member]

ok will do, Oh other question you said the port might be a little slim if they move a lot of air. The xmax on them is only 13mm so I dont think it will be to big a issue, but I welcome any advice on what to do with it?

 

[RAM_Designs 5,000+ posts]

You could do ports on each side that aren't so skinny in order to reduce the surface area inside the port. Go with 12"x4" or something like that. Just a suggestion.

For example, with a pair of 12"x4" ports you have 96in^2 on port area, compared to the 100in^2 you have now with the 40"x2.5" port...so pretty close as far as opening size is concerned. Lets say the ports will all be 20" long for comparative sake. With the single skinny port you have 1700in^2 of surface area inside the port. With the dual ports you have 1280in^2. So a hair more than 25% less surface area inside the port for basically the same port area.

 

[sackamous 10+ year member]

only question there is to use the box size i have now it would be 20*2.5 on each side instead of 40*2.5 across the back. I understand what you are saying about reducing the surface area, I would like to keep the subs centered across the front with the port area even for both sides of the truck. Would It make a lot of difference to put a square box port in the back corners of the box, say 12*4 like you said, or maybe 7*7 that would be 98 square inches?

 

[sackamous 10+ year member]

a port that would look more like this on each side is what I mean.

 

[RAM_Designs 5,000+ posts]

That would work. The only thing that might be an issue is how close the subs are to the internal port openings.

 

[sackamous 10+ year member]

would this work better?

 

[marcotheclepto 10+ year member]

would this work better?

possibly just want to make sure youve got slightly more distance between them than the width of the ports

 

[sackamous 10+ year member]

It's about 13.5 between they aren't completely drawn out but the block is the size of the opening 7x7. I can tweak to box a hair to get the room would 16 between be enough?