PCV system

[roortube]

My motor has been pushing oil out of the seals since it was new. Recently, my clutch slave took a dump, and now the clutch is slipping. Time for the motor to come out for a reslea and new disc. Ive been running an 034 catch can setup for UrS cars, and would like to design a better PCV system to minimize leakage on boost. Input or BTDT would be great.

[PRY4SNO]

There are a few big threads on QW about this.

Pretty sure morris400 was the most recent to ask, with a bunch of links provided.

HTH

[morris400]

I thought about running a catch can and deleting valves to create a more simple design. In the end I chose to keep it stock and replace the valves with new ones. All in all I found very little oil returning to the intake to begin with.

I ran a CC on my old B5 s4 and in winter it froze and and blew out all my top end seals...then the motor blew 2 months later. Probably not related.

The oem design works very well and I chose to keep it. CAtch cans pick up a lot of moisture and can freeze this time of year. I was told by a good friend who has made many Pcv systems, if your running a CC keep it near heat to prevent it from frezzing. The 034 design has it on the intake side...exhaust side would be better.

[UrSobsessed]

If you're pushing oil out of the seals, that much then it sounds more like the rings letting too much air by than a problem with the PCV system. The 'spider' coming out of the block on the AAN could have a larger diameter port to allow more air to escape to relieve pressure on the seals, which would help you also. Another help would be to route the cam cover vent directly into the CC. I know Pop on QW is having issues with the VC seals leaking from the cam cover getting too much pressure. He's also seeing ~20% leak down, which is his biggest problem. The stock system is pretty good considering it can handle RS2 boost pressures, but if you're hitting 30+psi, I can see where it would start to come up short...

[88a5tq]

I stopped blowing oil on my 200 after removing all the valves in the CCV system and venting the oil cap on the VC into the catch can I made. Alot of the pressure was probably from the 27 psi I'm running that's getting into the VC. While I was messing with the check valve, I decided to isolate the CCV line from the intake manifold altogether. Works very well. My new rear main became the primary leak after I completely resealed the VC gaskets with solilicone. I just had my head rebuilt and machined too.