HYDE161
Go Kart Champion
While this is true I still see a potential issue with running a catch can with the front and rear lines configured this way while still utilizing the OEM PCV setup. In a completely stock car at idle, the vacuum in the intake manifold pulls in fresh air via the front (manifold) line through the PCV from the rear line connected to the intake pipe just before the turbo. When a completely stock engine produces boost it closes the check valve connected to the front (manifold) line of the OEM PCV and the engine then draws the crankcase vapors through the rear hose connected to the intake pipe, effectively reversing the direction of flow between idle and boost conditions. With the modified routing of the APR CC setup (and other CC manufacturers), there is no fresh air being drawn into the crankcase at idle. Would this not cause a slight pull or vacuum in the crankcase at idle thus stressing the seals over time? Perhaps this pressure is negligible or I'm just flat out wrong? I've always been paranoid about the all-too common RMS failure and I really don't want to pull the trans to replace it. If that happened I would have no excuse not to do an LSD, clutch packs, flywheel and TCU tune at that point right?
I hope you follow me on this..... I'm hoping I'm missing something somewhere with how this works but I've played around with several new and used PCV units to figure out how it works. I really want to find the best fix to prevent oil build up in the intake track. I've pulled the boost tubes several times for random maintenance and oil has always been present. When I did a carbon clean I ended up replacing the factory intake manifold with the latest revision because so much oil was caked on the inside I didn't want to waste a bunch of time attempting to clean it all out.
You're 100% correct, blocking off the front of the PCV elevates crankcase pressure. I now run the ECS CC which has the best configuration, the only change is I had a 100psi check valve added into the connection between the PCV and intake manifold so the PCV gets it's vacuum but will not see boost (or boost levels on a big turbo that will break the PCV over time.