Prius C Subwoofer Box Fabrication/Install (kinda pic heavy)

Since I have the fiberglassing skills, I decided to finally get around to making subwoofer box for my Prius (until I decide which way I want to go in my SQ stereo setup, but it'll all be hidden). I had a cheap 8" Boss subwoofer and an Alpine amp sitting around I got from a friend a few months ago, so I figured I'd use those to keep my costs down.

The goals: to limit my loss of space, to get around .5 cu ft (ended up .45 based on a water measurement), and make an easily removable subwoofer box without affecting my ability to get to the spare tire.

I decided to tuck it away in the corner and hide the amp under a seat (no pics of that). I started by masking the area I was going to use:



After I had the area taped off, I pulled the panel from the vehicle so I could work on it with less hassle. I taped off all the 'holes' and sprayed it down with PVA (it's a mold release agent) then I used some high build primer to start making the base (for easier sanding later) :



After that, I laid the fiberglass to complete the 'form'...




The cured fiberglass popped right out of the panel. PVA is water soluble, so it sprays right off...after cleaning, the panel is in the same shape as it was before I pulled it out.




Then some trimming and the test fit, hoping nothing warped (it didn't)



Then making the plug...

Made a mold and popped the plug out (not usable after making the mold, which is typical).



After that comes the easy part, making the actual sub box...



Then final sanding and finishing...I use a truck bed liner for durability.



Installed with the temporary sub until I figure out what direction I want to go in the future (10" or 12"). I used the factory bolt to bolt it in and a couple areas of high strength velcro on the back side...it isn't going anywhere without some serious yanking. You may notice the light above the box, it's from a light I got from a Pontiac Aztec and wired in on each side...put some bright LEDs in there and it really lets me see at night.



All-in-all, I'm pretty pleased with how it turned out and it really fills in the lowers frequencies that the factory stereo just can't get to. If I were to do it again, there's a few things I would change, but since this is temporary (for the next year or so) it's not really worth the time.

 

Very nice...I’m going to go with a 6 channel amp and put some mids in my pillars, separate amp for a sub as well along with DSP, etc,etc. All long-term (over a year) plans