Q: I need to isolate my intake from the PCV system

asked by on September 20, 2016

My car is highly modified with a supercharger, complete exhaust and more. I've been advised to isolate my intake from the PCV system to prevent oil mist from flowing into my Supercharger and intercooler. To do this I've been told to run 2 catch cans vented to atmosphere. The first one from the Valve Cover and the second from the PCV valve on the crank case. My concern is that running vented to the atmosphere will create no vacuum in the system as it does in stock form. Is this problematic or will the engine run safely like this? One specialist in Miata's advises me to do this, and another claims it will cause problems with the bottom end and piston rings not seating correctly. I've scoured Miata forums and done google searches and keep finding conflicting information.

My car has 20000 miles.
My car has a manual transmission.

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