Why?

[Fatty]

Is it just the photo, or my eyes, but I don't see any side-impact bars protrusions in the doors. I hope this is a non-Aus model.... or did NA6's not come with side-impact bars?

side impact bars were fitted to aus delivered cars.
also, regarding the eunos roadsters that have since been imported, part of the compliancing is to retrofit side impact bars.
my aus delivered na6 has a jap door (coz i bent the original one) that has a new bar welded into it.

[Fatty]

Article calls the car a miata and thats definitely a yank tank behind it. not Aus my guess.

Cheers,
Julian

and yes you are correct, that article is taken from an american book - "mazda miata performance handbook"