As far as I am aware there is no specific induction kit. Keith Hofgartner describes a DIY improvement on his "LeMans 62" page here
http://www.lemans62.org.uk/Tips.htmlLike many others I have fitted a K&N high flow filter in place of the standard paper filter - this helps, but the route for the air intake is poor.
Best mod for the 1800 blacktop Zetec is a decent exhaust manifold and system such as Librands - though not cheap, this totally transformed my car.