In a message dated 1/22/01 10:36:40 AM Eastern Standard Time,
keith_adams@transcanada.com writes:

<<  This catalyst causes a reaction on it's
 surface which converts nasties (oxides of nitrogen as monoxides of carbon,
etc)
 to their fully oxidized (and less harmful) states.  >>

So then why would it be a factor in fuel economy? Being that it is in the
exhaust, the fuel burned by the van would be used before that.

--Paul--