As per this question and response:
http://www.zcar.com/forums/read/1/1828611

This contradicts the engine-bay cleanup sticky, relating to putting a breather on the valve cover. Can anyone elaborate?

 

i have efi(ms) i have a breather on my valve cover. i see no real problem on mine.

not as clean as the other engine but it will be once i get her on the road.

 

Me too...

 

Indeed. I have been running with a breather for awhile with just the stock EFI and have not noticed any effects. Thanks for the confirmations.

 

np....nismo nice clean engine bay of course i would not expect anything less is that a pallnet or jsk fuel rail?

 

doesnt look like a pallnet. is yours a pallnet though 260? looks just like my pallnet chilling in my closet.

 

si, he lives 45mins away from me,done alot of jy shopping with him.

 

I believe it's a Pallnet. I got it from a guy on ebay parting out his Z.

 

I had never heard of the PCV connection being a problem. I suppose I could see that if the crankcase air was connected to the valve cover. Its basically is since the crank, oil pan, front cover, head, valve cover all has an open chamber where the timing chain goes. Makes sense now...

But I also ran the filter for a short while. I only did that so I could dump recirculating air from my BOV back into the intake tube that the valve cover vent hose went in. When I got a BOV that vented to atmosphere I reconnected the valve cover hose. Seemed to run fine in both cases. I didn't get terrible gas milage.