engine 'breather' systems

[Peter Kemos <peterk@xxxxxxxxxxxx>]

Happy New Year to all you Alfa people out there!

Upon reading David Anderson's post about a '67 GTV for sale I took a
look at his site and the pictures.  This lead me to something I've been
pondering for a while:

My '73 Spica GTV (cast my vote for mechanical fuel injection, properly
set up, starts every time rain or shine or fog or whatever..) has a
stock engine breather / oil separator system which consists of a fitting
on the pass. side cam cover with a hose running to the oil separator
cannister mounted on the firewall. 

I do not find this to be particularly elegant however, since it clutters
up the engine compartment and has hoses running all over the place.  The
function seems contrary as well; on the one hand oil is expelled and
re-routed back to the sump, otoh air is drawn into the separator from
the air box, due I suppose to engine vacuum, but then I'm told the
device allows built up pressure from blow-by or whatever to escape as
well.  So what is it, is it sucking or blowing? (yes, I know, no
shortage of cheap jokes there.... ;)  

Ideally I'd like to get rid of it.  I believe that early 105 cars had no
provision for this whatsoever, and now looking at David's web page
reminds of numerous racers I've seen which have switched the breather to
be incorporated into the oil filler cap.  IAP has yet another gizmo
(depicted in their catalog) with a small air filter assembly attached to
the cam cover breather fitting. 

Sooo, 1) what does the separator really do? 
      2) what are the pro's / con's of the oil filler cap
breather               and/or IAP's filter assembly?
      3) where is the hose from the oil filler cap breather routed?
      4) what's a guy to do?

Sorry for the long post, have a nice day.

Peter Kemos

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