I saw a thread a while back. this guy had a catch can with 2 lines and a filter. one line went to his VC, then the other line went off to his breather box on the back of the block....its that SAFE to do? it just doesnt sound right at all

 

it is ok, depending a bit on how you drive, where you drive, and how often you change your oil. Without a PCV you can get a bit more moisture in the engine, and a bit more blow-by contamination. If you live in a cold humid area, rarely change your oil and drive 5 miles to work then park, the water will not have much opportunity to get out, etc. btw, most people with high compression run this way because they really don't want oil in the intake (very low octane).

 

Oh, I misread your post. So he would have pressure in the block then? Maybe I don't understand what you're saying, but if you seal off the block then blow-by will pop out the dip stick or possibly some seals. I thought you were saying that the crankcase had a vent but it was not connected to the intake manifold...

 

no actually you kinda had it the first time..


the guy had the breather box on the back, a hose that ran from that box to a oil catch can, then the catch can had another line that went to the valve cover...of course the can had a filter on top. here is a picture of it (sorry for the horrible pic lol)

but it goes fromthe breather (blue)
to the catch can
from the catch can to the Valve cover (red)


maybe that can explain it better for ya. thanks for atleast replying to this lol

 

All a PCV system does is vent off unwanted crankcase pressure. For Emissions it is routed back into the intake manifold so the bad air can be burned pass through your cat.
Eliminating the PCV system and putting in a breather can is fine He just did not want to have really hot dirty air flow into his combustion chambers. Keeps the inside of intake manifold cleaner too. Still being debated weather it truely helps performance. in theory it should.

 

thanks man. I always thought that the PCV was like a pressure regulator for the crankcase....but ya that makes sense....i would rather have the PSV missing so i can keep it clean, and keep moisture out of there...thanks man!