In order to make more room in the tiny Miata trunk, one can relocate the spare tire under the car, but only if you get another muffler. See here how I did that.

I got a 1st generation Isuzu muffler (#h3d 6773m) from Midas and had it mounted at an angle that would allow me to mount the spare under the car:


This is the new muffler before I installed the spare next to it.


As you can see, the spare is tucked in there very snuggly and completely invisible, if you're not lying under the car.



I used a locking nut with a clotter pin to secure the tire. The bolt was mounted in one of the drain holes with a pair of big fender washers and a locking nut.


And the trunk looks so much bigger now without the tire. That spare sure has annoyed me quite often until now.