My port calc just doesnt seem to add up

[GI JOEY 10+ year member]

4.35 after DD and estimated port displacement. With a 4" round port I am getting only 4.68 to tune to 32 HZ. What do you think. This is in a truck under the seat side fired port drivers front firing. This just seems off to me.

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[thehardknoxlife 10+ year member]

I get 4.9, but I suggest at least 2 4"ers. 3 if possible.

 

[GI JOEY 10+ year member]

If I had 3 4"ers what would the lengthe need to be on each? I might be able to do it. Here is what I can do. This is just a rough draft of the box to show what Im talking about. Without port displacement this box is at 4.5 and I am looking for around 32-34.

 

[GI JOEY 10+ year member]

OK I found a better calc. I am getting 17.5" long 4 inchers in a treo for 33.25HZ. I am just getting a rough idea for now. I am building the box now and part will be fiberglass so I will have o fill it with sand. If I get stuck Ill be back.

 

[thehardknoxlife 10+ year member]

If I had 3 4"ers what would the lengthe need to be on each? I might be able to do it. Here is what I can do. This is just a rough draft of the box to show what Im talking about. Without port displacement this box is at 4.5 and I am looking for around 32-34.

I would just get 3 aeros throw them in the box. No cut, no anything. It would be around 4.1 @ 33hz giver or take.

 

[GI JOEY 10+ year member]

aeros would be nice. How long should they be? I have never used them. I have always gone slot port.

 

[thehardknoxlife 10+ year member]

aeros would be nice. How long should they be? I have never used them. I have always gone slot port.

They are 18" end to end out of the box. Don't cut them, just throw them in the box you have and it will be pretty darn close to what you want.

 

[GI JOEY 10+ year member]

The ones I am finding on parts express are only 17 inchers. You know of another place to get these?

 

[GI JOEY 10+ year member]

I hate this Fing search button not working. I know it is posten here somewhere but I cant find these ports anywhere by searching google.