Thanks sridgett, thanks bav!
The ST170 is a zetec based Mk1 in the US; it's called a SVT (Special Vehicle Team).
Both my cars are Duratec based -- the grey one is a 2.3L, the red one is a 2.0L.
The red one will be getting a ported and polished 2.3 head though and we're going to port match the Cossie IM. Should flow pretty well