Securing the removable subwoofer box

[M3 Pete]

I have an E36 M3 sedan with fold down seats. I'm about to get a 10" sealed box for a subwoofer that I want to place against the rear seats. I want to be able to easily remove the sub box to use the fold down seats, but I need to secure it for canyon runs, freeway onramps, etc.

I was thinking of mounting it to a piece of plywood that is just wide enough to fit between the wheel wells, which will hold it from side-to-side. To secure it front to back, I was thinking of a ratchet strap, but not sure where to hook it to. I could also put in some bolts from the underside of the trunk sheet metal, close to the wheel wells so they won't be in the way too much, and bolt the plywood to that.

What have other people done? I have heard of people replacing the spare tire cover with plywood or MDF and attaching the sub to that, but then you have this massive piece of wood with a sub box attached to it to remove and then where do you put it if you need to use the fold down seats and are not at home?

[hli]

Perhaps Velcro? That's what I used in another car and it worked great on that car's carpets.

[Moron95M3]

Mine is in the back left corner of my trunk. Just a standard walmart 10" box. I added a piece of plywood to the box that extends upwards to the top of the trunk 'roof'. This keeps it vertically put, and for side to side, I have a ziptie through said piece of ply wood and that zip ties to the trunk 'roof' (I think I did drill 2 holes). As for fore-aft motion, it kind of stays put on its own...and the zip ties helps. Painted it all black and it doesn't look bad compared to a big ugly sub being there in the first place.

So when I got AutoX...I just cut the ziptie, and rotate the entire box out of the trunk. (and undo the couple wires).

It's been exactly all that I wanted.

[Midnightfreak12]

Pics?

Mine is in the back left corner of my trunk. Just a standard walmart 10" box. I added a piece of plywood to the box that extends upwards to the top of the trunk 'roof'. This keeps it vertically put, and for side to side, I have a ziptie through said piece of ply wood and that zip ties to the trunk 'roof' (I think I did drill 2 holes). As for fore-aft motion, it kind of stays put on its own...and the zip ties helps. Painted it all black and it doesn't look bad compared to a big ugly sub being there in the first place.

So when I got AutoX...I just cut the ziptie, and rotate the entire box out of the trunk. (and undo the couple wires).

It's been exactly all that I wanted.

[AJLM34A]

Did you buy a box already? I made a box that sits over the battery and can be secured with an L-bracket that bolts to the factory CD changer stud. I did shave down the tail light bulb cover and a few of the sockets to get the most air space.

IMG_5755.jpg

[Moron95M3]

Pics?

It takes up a bit of space...but not enough to be a pita. Pardon the dirty filty car...It's been way too long between cleans

IMG_7976.jpg

[callison157]

Did you buy a box already? I made a box that sits over the battery and can be secured with an L-bracket that bolts to the factory CD changer stud. I did shave down the tail light bulb cover and a few of the sockets to get the most air space.

IMG_5755.jpg

Wow, that is really nicely integrated. Would you mind sharing more info on how it was built; box dimensions, amp and sub specs, etc?

Also wondering what you guys think of the sound? In my previous research on this I read that the trunk is so well sealed that the bass doesn't really come through with the sub in the trunk, so I'm curious what your experiences are.

Hope this isn't too much of a thread-jack.

[Midnightfreak12]

Not bad, mine is smack dead in the center of the trunk... holds in place because i have my tool box right infront of it so nothing can really move lol. I for some reason cannot bring myself to not bring a toolbox with me at all times :/ especially during canyon drives.

It takes up a bit of space...but not enough to be a pita. Pardon the dirty filty car...It's been way too long between cleans

IMG_7976.jpg

[realjones]

I have a box from BSW that hangs off of the rear deck. Very secure. Been there for years with no issues. I don't think they make it anymore, but there's nothing bespoke about it...mounts with L brackets and some star knobs. I also removed the rear speakers to port some bass into the cabin to counteract how sealed the trunk is (as you mentioned). You can still use the fold down seats with the box in place.

Not mine, but you can see the general idea in this thread:
https://www.bimmerforums.com/forum/s...for-E36-coupe)

[Carpy2]

I have two 10's sitting right behind my back seats as well. Ignore the need for me to carry coolant in my trunk...
IMG_0413.jpg

I use velcro and it's held up perfectly fine. Something like this at each corner: Amazon Velcro Link

The only thing that may happen is the velcro and the velcro's adhesive may be stronger than your trunk mat's fibers. I ruined one corner's velcro and just never replaced it, three corners is enough :P