[s-cars] Why S4?

[Kris Pruden]

I found myself wondering about the name "S4" the other day, and though
that someone here would probably know the answer to my question.

My question is: how did Audi come up with the name S4?  I know that
the model on which the UrS4 is based was labeled the 100, and the
smaller sedan the 90.  In '95 they switched to the A4/A6 names, so the
change to S6 in '95 makes sense to me.  But why S4?  I'm pretty sure
the S is for "Sport."  Is the 4 for 4 doors? 4-wheel drive?  Am I way
off?  Perhaps I'm overanalyzing and the Audi marketing folks just
though S4 looked cool.

Does anyone know?

Thanks,

Kris