PDA

View Full Version : Built new box, what port config.



skylineTT
06-26-2011, 11:53 PM
Built my truck box today. 1.5 cubes after sub displacement.. if i do a 4" ABS port, how long will it have to be to get 29hz tuning mounting it inside the box?

i figure at 25", it will consume .15ft^3 of space making the box volume 1.35 internally, making the tuning close to 29. I am unsure if i did this right, and also if my sub will be okay in only 1.35 cubes. :P can anybody clarify this for me? thanks

also, the top depth is 4" and i wanted to upfire the port but it doesnt look possible so i thought about firing it to the passenger side, but it will be about 1.5-2 inches away from the wall. should i just go ahead and side fire it anyway? thanks

Kangaroux
06-27-2011, 12:06 AM
what sub?

skylineTT
06-27-2011, 12:59 AM
its a custom 10 by Corey. Type X motor, 2 med spiders, high roll surround, 3" coil for 1000rms+/-

kushy_dreams
06-27-2011, 01:25 AM
In 1.5 cu/ft with a 4in port the length needs to be 23.91inches for 29hz tune

In 1.35 cu/ft with 4in port length needs to be 26.9 for 29hz tune

skylineTT
06-27-2011, 02:55 AM
Right, but is that with the port inside still? I always thought port volume took away from box volume. Either way though, would side firing that close to a wall even be effective?

Buck
06-27-2011, 09:11 AM
You usually figure this part out before you build the box.

skylineTT
06-27-2011, 11:55 AM
too late and it wont make a huge diff. ill probably do around 25" and side fire it. That's about the only option I have.

jalm
06-27-2011, 01:18 PM
If its close to the wall it will basically be like the port being a little longer outside the box. How to figure that distance out I dont know. Will probably be tuned just a little lower when in place, if any.

Phoenix Risen
06-27-2011, 01:21 PM
If its close to the wall it will basically be like the port being a little longer outside the box. How to figure that distance out I dont know. Will probably be tuned just a little lower when in place, if any.

with the port too close to a wall the port acts like it is a smaller size. which in theory will lower the tuning but could result in "port noise" because the air is hitting a choke point.

skylineTT
06-27-2011, 04:35 PM
hmmm this is good info. Thanks

guess ill go ahead with a 24 and just see what happens. I will let you foo's know!

Buck
06-27-2011, 05:03 PM
With the aero, you can always cut the length down.

skylineTT
06-27-2011, 06:17 PM
true that, ill use a flare on the inside as well to make it "less turbulent"