View Full Version : round port help

11-23-2011, 10:49 PM
Running a DD508 in a reg cab ranger with about. 8 cuft need some opinions or help on round ports. I've checked on some online calculators and for a 1.5" diameter port it should be 3.5" long would I be better of off running a larger and longer port for lower frequencies?

11-23-2011, 11:14 PM
the general rule is 9-13 square inches per cubic foot for round ports. you are around 2.2 sq in for the .8cft box. go with a larger diameter to keep port noise at bay.

11-23-2011, 11:53 PM
I have a 4" port I'm gonna sell

11-23-2011, 11:58 PM
What are you tuning it too, 41hz? PSP-inc.com says for .8 ft ^3 a 3.5" flared port tunes to 41hz. If straight port its 36hz.

11-24-2011, 01:09 AM
If space is a real issue, spend the extra on flared aero's. They don't make a more efficient port..

11-24-2011, 08:11 AM
For a tune of about 41Hz I'll have to run a longer port with a 3" port diameter


For a tune of about 36Hz I can run the smaller/shorter port


The main reason i was going with the 1 1/2" port is b/c I can run it out the top of the box unrestricted if I run the 3" I'll have to run out the front of the box which will be about an inch from the back of the seat. If someone could double check my figures for ports that would be great. I want this to hit LOW and LOUD