OK, I wanna make a custom trunk setup for my car. How can I build a box with 2 12's in the bottom of the trunk, facing up, and going down into the spare tire well? I wanna do this, and mount my spare wheel and tire on a shelf or something after, and an amp. Maybe a dvd player, and some tv's. Anyone have a write-up on doing the sub setup tho?

i guess the first question would be: have you ever worked with fiberglass?;)

doing a false floor with subs in it isnt that hard, but can be tedious to explain. i would suggest going to sites like www.sounddomain.com or www.termpro.com and clicking on thier forum sections, then searching for somthing like "fiberglass spare tire" or somthing. do a lot of reading and youll learn a lot.

basically the steps are this:

1) remove the spare tire and mounting brackets for the jack and tire (with a neumatic grinder of some sort).

2) lay down either (a) mold release wax (b) duct or masking tape (c) aluminum foil (d) plastic tarp or (e) any combination of the above in the spare tire area and along the floor. make sure that it is steady and contures closly to the curves of the spare tire well.

3) create a square (doesnt have to be square, but i'll simplify it;)) frame out of 2x4s or similar to fit around the outside of the tire well. basically, this is the structure that the fiberglass will adhear to around the outside of the well. if you can imagine looking down from a birds eye view on the spare tire well, it would look like a circle. you want to construct a square that would fit around the outsides of the well. if you are using more than one sub, increase the width of the frame to compensate for the extra speakers diameters. if you are using for example 2 12"s, you might make the frame 30" wide and 15" high, so that the 12"s will fit without a problem. to increase airspace for the speakers, make the frame taller vertically. drill a small hole in one side of the frame to run speaker wire through later.

4) lay fiberglass down in the wheel well and smooth it up to the sides of the frame, so that it all becomes one piece. after 2-3 layers of this, you should be able to remove it all from the car. lay down another 3-4 layers untill the fiberglass is about 1/3"-1/2" thick. i could write pages on how to lay fiberglass, but youre better off researching it yourself;)

5) create a false floor panel that will fit over the top of the fiberglass/frame piece. cut holes in it to mount the subs in.

6) with the tire well section in the car, lay the false floor on top and drill holes to mate the two pieces. lay down a bead of wood glue and screw the pieces together. carpet/vinyl/paint and screw the subs into place.

thanks.

I didn't think it had to be fiberglass? Thought u just had to seal it??? I just want something with 2 subs facing up. So I'll have a little trunk space instead of the ugly box that slides around all the time.

it doesnt have to be fiberglass, but you will loose a lot of airspace if you just want to use MDF.

MDF??? I'm basically a newbie as far as ICE goes. It might take me a while. How hard is it to fiberglass it?
MDF= wood-like material???

man, i feel your pain.;) when i first started reading this board, i was like "boost?...compression? whats all that?!?!" LOL. i still have no clue when it comes to engines, but im trying to learn!

MDF= medium density fiberboard. its kind of like plywood, but with finer particles of wood to make it denser and more durible. its heavy, cheap, and strong...perfect for box building. if youve had no experience building boxes before, visit the two sites i listed above and read up a little on it. www.sounddomain.com has a ton of install pages that show step-by-step installs, so that will give you a good idea of what goes into it.

BTW to all the mods, let me know if im not supposed to link to other message boards or anything. im not trying to advertise or anything.;)

I'm gonna try usng MDF. It shouldn't sound any worse than it does now imo. I need black trunk panels or need info on wrapping plastic panels in vinyl.

only way to have it sit in your spare tire well is gonna be to use fiberglass, you won;t really be able to get enough airspace for much of anything trying to use just MDF and have it drop in that area. If you decide to glass it and cut the jack mount out then be careful when you do it and make sure to drop some silicone and undercoat form the underside of the cat if you pop any holes though, that metal isn;t very thick down there...Just follow the instructions listed above for doing the glass work....and for the part that drops in your wanna use something durable like some tiger hair or something so it will handle the pressure from the subs. Either way good luck....

Then agian, if I keep getting these crazy ideas mine might be for sale in the near future to cut down on weight.....

how do you form the fiber glass? and how does it seal to the box at the top?

Easiest way is when you form it to the tire well, bring it up over the edges some to make like a lip that is about an inch wide around it. that wat when it dries you can drill some holes through and mount the layer of MDF to the top and screw it down onto it. Make sure that when you mate the 3 together you use Liquid Mails in the joint where they come together and then run a healthy bead of silicone around the inside to make sure you seal it up. Another bit of advice that I did is to dropa set of banana plugs into the side of it to aid in speaker wire connections, that way you can seal it up where you put them in at and not have to worry about any leaks. Not sure which subs your running but my best guess on mine is that the finished product will give you roughly 3 cu ft of airspace in there which is why I had to run my subs isobarically since they are air hogs.

I found a shop that does them for $400. My friend got them to do it for 200 b/c he knows them. He's gonna ask them how much I can get it done for. I figure it would be cheaper to have them do it, since I'd probably end up redoing it a few times to get it right. Cost of materials would get up there eventually.