View Full Version : need help designing a box for my 4runner!

04-21-2009, 10:40 PM
i just sold my civic and got a 4runner, so i have alot more room to work with.

i can use these demensions..

39 inches(side to side) x 32 inches(front to back) x 20 inches (tall)

box for 2 15" subwoofers, btls most likely as thats what ive worked with before.

i want subs upfiring and port shooting into the hatch.

if someone can design a box like this for me let me know, free or charge i got some money in paypal if needed.

let me know box designers!

04-22-2009, 12:56 AM
Alright, here's what I designed according to the thread/pm you sent me.

Here's the box unfinished but with walls and ports installed. So you can get an idea of the port structure


Here's the box completed with X-Ray walls on and the dimensions. I'll explain all dimensions at end of post.


Finally, here's the finished product with a simulated carpet/wood texture and little Fi logo that is raised to give it some "pizazz" :D


Alright, here's the exact spec's of the box.

The box is built for two fully loaded 15" Fi BTL's

Double top baffle for flush mounting the woofers.
3/4" MDF construction
--Dimensions (External)
Width: 39"
Height: 20"
Depth: 32"
Port: 4" x 37 1/2" for a total of 150 sq. in of port area (no port noise :))
Tuning: 32.6Hz (I know you said you wanted 34Hz but keep reading and I'll explain)
Fi Recommends 3-5 cubic feet per sub in a ported enclosure.
Net Volume (with port subtracted) 8.62 cubic feet. Each 15" BTL takes up 0.21 cu. ft... so with both BTL's loaded into the enclosure, the total volume will be 8.2 cubic feet. With the subs loaded, the tuning becomes 33.4Hz.

I still tuned just slightly lower and over 8 cubic feet, and that is because this does not factor in any internal bracing. And since you are using a fairly large enclosure with high power, high SPL subs, adding dowels or some kind of bracing is highly recommended. This way, once the bracing is added, the total volume should be very close to 8 cubic feet total (4 per sub, right in between Fi's recommended 3-5 cu. ft) and the tuning should be 34Hz on the money.

I need some sleep, I've gotten so many box design requests in the past week, I've been stayin up too late doodling on google sketchup lol.

Good luck with the box build Exxdine, and pls take vids :D

04-22-2009, 01:05 AM
looks nice and correct. good design bro

04-22-2009, 01:11 AM
looks nice and correct. good design bro

Thanks :)

04-22-2009, 07:57 AM
yeah man that looks excellent