Custom Car Boot Install

Mazda3 Boot Stereo Install with false floor and amps

The day after we purchased the 2004 Mazda3 Maxx Sport, it was clear that the factory stereo needed to go. Unfortunately, the sound quality was terrible. So a plan was hatched to add a whole new system to the car. This meant the boot had to change... a lot.

The Mazda3 comes with a great false floor in the boot, including handy storage space that is nicely hidden away. This was great inspiration for working out where to hide the EQ and Amps for the aftermarket stero.

The existing false floor is being replaced with a new, sturdy false floor which will be able to tilt, maintaining access to the spare tyre. It will house:

  • 4x100W Amp for component speakers
  • 2x150W Amp for Subwoofer (bridged)
  • 6 band EQ
  • 2 x Distribution blocks for power/ground
  • Storage hatch to stop small items rattling around the boot

The false floor has to carry around 15kg of wood and equipment, so getting the tilt mechanism to work safely is important. The trick is to anchor the pivot frame to the car using the rear seat bolts. Take an angle grinder to a corner bracket and use this to secure between the seat bolt and the pivot frame.

False floor pivot anchor

The corner bracket before drilling the hole for the second seat bolt (not visible).

Bunnings has some great all purpose car carpet which almost matches the Mazda's upholstery (it actually feels more durable). I tried a few ways of making it stick, inluding Selley's Glue (which was highly recommended for carpet), but the most effective method was actually Selley's Liquid Nails.

Upholstering the false floor

Tape it down with masking tape, and use a heavy weight to keep even pressure whilst drying.

The next step was to mount the equipment and run all the cables.

The equipment has been mounted and the cables have been run

Then screw on the top of the false floor.

False floor cover mounted

The white rope you can see in the center of this picture is what is used to tie the false floor down to the spare wheel - eliminating the need to add an extra screwhole to hold the false floor down.

Finally. add the access hatch and finished!

Finished false floor with access hatch