2 E8's ported enclosure assistance needed on Port Tuning

[jpmo]

Currently working on an Ported Enclosure for 2 E8's in my Jeep Wrangler JKU. I may move in the future to SA-8s but as of now the wife will hold me to the budget. So the following is what I am working with currently. I need help on making sure this will work for Cubic feet and need help on this port length. Please help.

Port have separator setting 2 chambers apart. 1.5 in width run to end of enclosure leaving 1.5 from back and leaving me with remainder on Port Extension Length I need help with this extension length to fit into the parameters of the E-8's

40W x12D x 10 H 2-8s

Wall Thickness 0.75 in

Front Baffle Thickness 0.75 in

External Width (W) 40 in

External Height (H) 10 in

External Depth (D) 12 in

Internal Slot Port Width (SW) 1.5 in / 38 mm

Internal Slot Port Height (SH) 8.5 in / 216 mm

Internal Slot Port Depth (SD) 26 in (?) not sure guessing please help.

Thanks for your patience and co-operation with this.

[jpmo]

Ok this is what I got so far I plugged all into torres and got the following 19.25 box width 9 H and 12 D. My port dimensions are 7.5 H and .5 Wide 13 long puts me at 34hz this port ratio is 1:15. Is this bad? This is for 1 Sundown Audio E-8 or SA-8 . My net volume is .58 cubes. The actual box will be 40 but putting in port wall leaving it 19.25 w per enclosure space. Thanks.

PS. I also calculated .10 for sub volume I noticed this on sundowns page for the E-8 but it says the SA-8 is only .08 strange would think the sa would take more room.