BC said:

>what exactly is the S2 engine anyways?  I noticed all of the completed
>production model Evas had one.  It's been a while since I watched the
>series so my memory's a bit hazy.

It stands for "Super Solenoid", and the theory of how it works was apparently
part of Misato's father's work. But as far as I can tell, it's a magic engine
that gives its owner unlimited energy.

--R.--