I have been investigating a new crankcase breathing set up that removes the PCV valves and creates vacuum in the crankcase for better performance, this is what I have found out through experimentation and investigation.

 

The Z has a fresh air purge for the crankcase via the front breather pipes, this will only happen when the PCV valves are open and creating enough vacuum in the crankcase to clear it through, when there isnt vacuum and the PCV valves are closed these front pipes re-route a small amount of blowby into the intake as the crankcase pressure has nowhere else to go.The front breather pipes can safely be connected to a breather filter and the connections on the intake closed off even on a standard system with no degradation of the breather system, the reason they are on the intake in the first place is for environmental reasons as its naughty to vent crank gasses to atmosphere.

The vacuum created by the PCV valves is necessary so you cant just put a catch can on the feeds and close off the PCV valves and leave it at that, the vacuum is necessary because without it the rocker area of the cylinder heads becomes the only place for the crankcase pressure to go( not good)

 

My solution to this is quite simple, I am fitting a electric vacuum pump on the crankcase PCV feeds ( from a ford cobra) which will run permanently to ensure a permanent vacuum ( only a small vacuum , not like the race vacuum pumps) , this pump will run via a catch can and will enable removal of the PCV valves.

 

Hope this saves anyone else looking at this some investigation and even some experimentation.

So are you saying it is ok to put filters on the front pipes, without the pump or with it?

its fine to put filters on the front pipes with or without the pump if you want to reduce crank gasses travelling in your intake when you are running on boost,when the pcv valves are open and the plenum is being used to crate vacuum in the crankcase the front pipes purpose is to allow a clean air flush as air from the intake is sucked down these just dont fit a catch can to the rear pipes as the vacuum created when the valves are open is needed to clear the crank through, if you do fit just a catch can the rocker covers end up getting a lot more of the crank gasses as i found out.

 

heres the page from the manual which started on my experiments

 

WOW!:confused: guess what you will be explaining to everyone at the next meet!:rofl:

 

dan.:smash: