March 18, 2025, 06:46:30 AM

Author Topic: SOLD: Custom 8" Sub Box for FD RX-7  (Read 1925 times)

Offline fastfalcon94

SOLD: Custom 8" Sub Box for FD RX-7
« on: June 17, 2023, 12:20:59 PM »
All boxes have been sold. Thank you.

I made a custom sub box for my 94 RX-7. I had half a sheet of MDF wood left over that I didn't know what to do with, so I decided to build two extra boxes to sell. One has sold already, so just one left.

About the box:

- Made of 3/4" MDF wood
- Black Sub Box carpet from Crutchfield
- Sealed Box
- Designed for JL 8w3v3 subwoofer (not included)
- Designed for JL 250/1 Amp (not included)
- Designed to fit under rear strut bar and conserve as much trunk space as possible (hence the offset sub and recessed amp locations)
- Weighs 19 pounds


I've been running this setup for about a month and love it. I always run the cargo divider and I haven't had any overheating issues even with the cover on. I have more pictures in my build thread:

https://www.norotors.com/index.php?topic=22607.150

Maybe even more pics on my website page:

https://802projects.com/blog/rx7audio/rx7audio.php

And a Youtube video that goes into a lot more detail:





Additional Details:

- My car has the factory OEM trunk mat which has the layer of thick high density foam under it. The box sits on the mat and gets pushed down slightly and slid under the strut bar. I use two tiny strips of wood (one on each side, roughly 1/4" tall x 3/4" deep x 3" long) covered in extra sub box material to wedge the box down. This takes the stress off the hatch cover clips that attach under the strut bar. It also provides a 1/4 gap under the center of the bar for more airflow to the amp. If you have an aftermarket trunk mat that doesn't have the thick foam liner you'd likely run into problems and have to space it up. I'll include some wood strips and extra box material for you to make your own spacers.

- JL changed their amp design. The mounting points were metal ears on the old version and on the new version they are solid plastic. My box was designed for the old style. However, based on the dimensions listed on Crutchfield; the new amp is slightly smaller and should work fine.

- The sub hole is ~ 7 3/16" inches. It's meant for the JL 8w3v3 sub woofer. I can't guarantee other subs will fit. The box is also designed for the 0.3 cu ft air space dimensions JL specifies.

- If you want to continue using your factory hatch cover, the front edge of it needs to be cut so that it can flip up. Otherwise the front edge of it will hit the sub box. I explain this in the video.

- If you don't like the price or would like to build one yourself, I have the dimensions listed in the video. You'll have about $120 in material and only use about 1/3rd of it. I don't expect to make any more. I just didn't want to half more than half a sheet of MDF kicking around for years to come. I have about 6.5 hours into this box and that is after already building one.



PRICE:

Asking $300 + shipping. I just boxed it up this morning. 33*11*13 @ 27 pounds shipped from 05468. Again this is just for the sub box. You'll need your own amp, sub, wiring etc... Any questions please let me know.

EDIT: Box has been sold



Pictures:



















Pictures showing the AMP revisions and dimensions. I have the old style:

« Last Edit: September 21, 2023, 08:35:10 AM by fastfalcon94 »

Offline fastfalcon94

Re: FS: Custom 8" Sub Box for FD RX-7
« Reply #1 on: June 17, 2023, 12:21:25 PM »


Pictures of identical box I installed in my RX-7:
















Offline Turbotronic

Re: FS: Custom 8" Sub Box for FD RX-7
« Reply #2 on: August 09, 2023, 06:25:49 AM »
That is slick. Solid work.

Offline blacksi

Re: FS: Custom 8" Sub Box for FD RX-7
« Reply #3 on: August 12, 2023, 08:18:55 PM »
Well, you inspired me but I am a do it yourselfer! When I got done spending my whole Saturday building this box I was thinking how much damn easier it would have been to send you $300!!!!!!!!!! 

One thing I did mod, was the added 5 1/4's and wow!  I never had a working Bose system so my stereo has always sucked and now it sounds amazing.  I think the angle of the back glass helps project them like they are pointed towards the front.  The divider thing covers the amp and I will clean up the wiring once I get the final parts of the build, see below.

Oh yeah I ordered the cheapo speaker connectors off amazon and the metal spade connectors were so thin they would not even hold a crimped connector so it is just wired with holes now until a get a better quality set.  They were ridiculous like 3 sheets of tin foil pressed together type thickness.

Oh yeah I have to find a new way to mount my meth container...
« Last Edit: August 12, 2023, 08:26:25 PM by blacksi »

Offline fastfalcon94

Re: FS: Custom 8" Sub Box for FD RX-7
« Reply #4 on: August 14, 2023, 07:15:23 AM »
Yeah the first box you ever make will take longer. I've made 3 at this point and it takes me 6-7 hours still from start to finish. Maybe if I were mass producing then and making the cuts for multiple boxes at once I'd save some time with saw adjustments. If you subtract materials and do the math... I make much more just working at my desk job. That's why these will be the only boxes I ever build to sell. As of right now...

 
1 is in my car sounding good
1 is sold to a happy buyer
1 is packaged up and ready to ship as soon as I find a buyer.