Any aero advantage to small skirts vs.
Tupperware skirts vs.
no skirts?

Time Trial vehicle in question otherwise stock body.
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Your question is extremely vague. Find examples and post pictures.

 

I understand this post.

In 1999-2000 NB1 (or so) they had an option on NB miatas for a side skirt body kit (and front lip)
He is calling these "Small skirts"

In 2001+ NB2 the side skirts got very large. They are often called "Tupperware"

I think in all years these are a dealer option and no skirts is available (and often the more common setup)


I don't know the answer to your question, but my hunch is that any side skirt will provide small amount of additional downforce as the body is basically lower. It is likely pretty minimal.
I would highly doubt a difference between the NB1 and NB2 skirts.