This can be done in almost any car. Best usage is for hatchbacks though. I have

personally seen it done in my '89 GT, a '93 Probe and an '01 Celica. The advantage to

this type of enclosure is severe weight reduction and saves a lot of space. Not to

mention that you would probably score some major points in a stereo comp.

The 1st thing you want to do is remove your spare tire & all of the equipment that

goes with it. You then want to vacuum out all of the dirt, garbage & crap that has

gotten into the spare tire well. After cleaning it out, wipe it down with a wet or damp

rag to ensure cleanliness.

You may at this time begin pouring water into the well to measure how much air space

you have. My figures have told me that there is about 2 cubes of air after you seal

the enclosure.

Now buy a rattle can of noise blocker that you can get from most any car stereo shop.

You will need to make sure to get as much of the noise blocker insulation out as you

can. Make sure to coat the entire interior of the spare tire well. I was able to get

away with just using one can. However, I would suggest using 2. Let that dry & then

continue.

You will now need to purchase a large piece of 3/4" MDF. Once you have measured and

cut the MDF down to a size and shape that will fit over your spare tire well, you will

want at least a 6" space of overlap beyond the exterior of the spare tire well, coat

the area where the MDF will be in direct contact with the metal of the hatch area

with calking, preferably a white plumbing type. Make sure that you have already cut

the hole in the MDF for your subwoofer. Before the calking has a chance to dry, using

self tapping screws to secure the MDF to the car. Make sure that the screws are

about 1/2" longer than you need to get through the MDF & your cars sheet metal. Put

a screw in once every 6" or so all the way around. Make sure to seal all joints & areas

where the MDF makes contact or there is a gap to seal it and prevent air leaks. Let

that dry for 12 to 24 hrs.
 

After it is dry, measure the space between the bottom of the tire well to the inside

of the MDF. Now cut 2 pieces of 2x4 and screw them into place with a screw through

the top of the MDF and one through the bottom of the tire well. These are stiffening

braces that will prevent excessive noise and flexing of the sheet metal.
 

Now, depending upon the size of your subwoofer and it's requirements, you may be

able to get away with just using it as a sealed enclosure. However, I was unable to do

so. I used a 9" long port 3" in diameter to get the proper sound out of it. I am also

running a 12" Rockford Fosgate HX2. All of this will now need to have the finishing

touches, such as carpeting and running wires. I used the hatch carpet & just cut holes

in it for the subwoofer and the port. Some of you won't mind doing this and some will.

At this point everything is up to you for your own personal preferences. Now the

weight of this whole install will probably be equal to or less than the weight your spare

tire was taking up.
 

If you want to keep your spare tire, I would suggest doing a custom mounting or

secure it to the side somehow. In my personal experience, I have only needed to use

my spare tire 2 times & that was when I had old worthless tires on my car. If you

have good tires and are a reasonable driver, you will probably never need to use it.
 

Well, that’s it.

Port in	Port out	No carpet	Support brace