Installed an FJ Cruiser woofer box in the 4R. I have been thinking of plans and ways to build a box. None of which made enough sense to take beyond planning. I really wanted to take up as little interior space as possible. Then I remembered this box. I had planned to wire and use it only as a test/proof of concept. But it sounded good and when held up to the storage area looked like it would fit just fine. So, no crappy box to build, I already had a good one I could use. Luckily the FJC and 4R are very much alike.
The FJC currently has a 12" Alpine woofer and an Alpine amp and enclosure. So this box was going unused and already had a Kicker 8" Comp 4 ohm speaker installed. I had already removed the stock joke-of-an-amp and speaker. Since I had to purchase a new amp, I decided to go full out and paid $53 for a BOSS AR1500M. Amp only has to handle under 40-50Hz so was not too worried about musical quality. How bad could it be? 2 ohm stable! And over 500 watts! Or more! Uh, yuh. It seems to do the job.

In order to get the box to set back as far as possible I spent extra time trimming what needed to be gone. Always a big thrill cutting into a relatively new vehicle. It worked, it fit. Sits over the wheel well area, and most of side storage area is still usable. The space/shelf under the box is partially covered and will surely collect all kinds of crap.

Will spare all the usual wiring details. Wired all the other wiry stuff, same as everybody else does, and fired that ultra massive, mega-highly-powered woofer up. Provides much more, and more decent sound than I expected. Looks great and is solidly mounted. And this combo is all the subwoofer I will ever need in the 4R. Honest.

Are you still reading? I hope so, because this may be the most interesting part of this install thread: I decided to use the rear speaker wiring as the location to tap into for signal for the woof amp. Not sure if this has already been done in this manner: I used the wires located behind the driver side D pillar. Looked at the wiring diagram and determined that the black/white pair and pink/yellow pair were the rear hatch speaker wires. Of them, Black and Pink are positive. This wire bundle is located directly behind where the black and gray D pillar panels meet at the rear hatch. Remove the bag hook and screw, pop the panels, and there you are. No need to disassemble the dash! And I was thinking that using the rear wires may have less of an adverse effect on overall sound. OK, the real reason I used these wires is that I am basically too lazy to take apart the dash.

Not much wire slack here and did not want to add much bulk to the wiring so I stripped away some of the wire jacket and tightly wrapped the new wires to the exposed area. Neatly taped them and popped the panels back in place. Should have soldered them, but, remember, I am somewhat lazy. One day I will.


Are you still with me? No need to continue unless you also have an unused FJC woof box that needs a new home in your 4R. The FJC box sticks out on its rear side and needs to fit into the storage area. That protrusion is one of the reasons this box has decent volume. Mark the rear hatch area that needs removal. Commense to removing this stuff from the side panel.


Remove these bits from the bottom of the FJC box and patch the now gaping hole.


Remove these from the back of the FJC box.

Grind, cut, chew, and bite to remove material to make the box sit back and flush. Fill resulting gaps with foam.


Still here? OK, back to useful general information. Use the party mode switch blank and location. Remove what is not needed. Disassemble new, included woofer level pot and place into switch blank. Almost done.

And here's a video of all the woofer wiggle jiggle.

whatever floats your boat I guess

Yes, how unusual it is for someone to install a subwoofer.

I wasnt referring to what was done as much as how it was done. If you are happy with the outcome thats all that matters

I'm surprised no one has turned the cubby into a sub box for a single 8" yet...

I thought about it, but there is not much room behind there. The lack of usable volume is one of the reasons the JBL set-up doesn't have much woof to it. And the curve of the 4R panels is difficult to overcome. Flat surface would be much easier to work with.

The first pic is the finished product or is it just sitting on the wheel well?

Both. It is sitting on the rear edge of the wheel well (the fifth photo shows a piece of rubber mounted to cut down on possible movement and creaking) but it is also nearly flush against the side panel behind it. The photo distorts it a bit. The second photo shows how it is square to the side of the vehicle. The side storage is still usable behind it. I could have mounted it a bit higher, off of the wheel by about an inch, but think that covering the tray on top of the wheel well was a better execution. The tray doesn't securely hold much anyway. If the wheel well didn't have that tray it would look more like a factory box. Just like in an FJC.
I would have liked to have mounted it further toward the seat back, would have been better if I could, but had to account for the recline feature.

Here is a photo showing how the storage space is still available behind the woof box. Also hows how the bottom of the box is flush to top of wheel well.

A sub under the drivers seat would have been another option. Not sure how I like the look, but as long as it does the trick....

I thought about that and investigated several. Was close to going that route. Was close to building one to custom fit and maximize space. The area of this box that fits into the fender area alone is larger than that of many under-seat boxes. An under-seat box cannot do what this box does. Just not physically possible. There are a couple of OK under-seat set ups, but this, in many ways is better.

To get the proper vocal range you'd need the woofer pointed up, which in my opinion would prove making it overpowered compared to the rest of the system and unbalanced to the other seats

Awesome.

I looked for a while but couldn't find anyone in Las Vegas to do the fiberglass work for less than $500 which is ridiculous for .3ft^3 box. I am still considering learning how to do fiberglass so I can make my own. It is the perfect volume for a JL 8W3.

With the right baffles, the lower opening could double as a port to get even more oomf out of a 8w3