Greg, thats a ford press release

Its a ZETEC. A Duratec is totally different, what it was, Ford were brining out these new Duratec Family of engines at the same time as the Focus ST170 and Focus RS, so for MARKETING and nowt else, they badged the ST170 and RS lumps (which are both Zetecs) as Duratec ST/RS engines

Marketing is to blame