I built one of these for my car and had built 3 others with the extra MDF I had left. Unfortunately it will only fit 90-93 without AC. The box is slightly too tall for cars equipped with AC. You might be able to modify the box slightly to fit in a AC equipped car. The box can be flipped to hide the subwoofer but might need a spacer to allow the subwoofer to move.

Internal volume is just under 0.4 cubic feet
Takes a 8" speaker
Top mount depth is 5.5" in the center
Top mount depth is 2" on one side because of the angle of the box.

The 8" pioneer shallow mount subwoofer I used fit just fine in the box.

I have 3 of these boxes

$65 shipped

Email: the80h@yahoo.com

 

I'm guessing you mean .4 cubic feet? Cool box.

 

You are correct.

 

I made one but the sub faces the front of the car or under dash area . I feel this is the best method to hear the bass frequency. Pointed out like your picture does not sound as well. The foot well sub box location is the best place to mount a subwoofer in a miata to get the best bass sound with top down. I have tried all other methods and nothing is better then foot well box. Anyways your box looks good. GlWS.

 

Up.

 

Ttt

 

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