So I finally got my 393ci windsor motor up and running. It's 10:1 with an XE284H camshaft. Currently only N/A. The motor only has 40minutes of camshaft break in and under 10 miles of drive time on it, but it has some blowby still, has gotten better, just believe the rings aren't seated yet. The rings were gapped for low 15lb boost, so .020" or so, would have to go back to my notes to find actual gap. Currently I only have breathers on the valve covers, no form of PCV system. What should I go with? I'm not sure how to properly pick out a PCV valve, since that's all dependent on engine vacuum. And I've read of people going with smog pumps that pull like 4" of vacuum, which is a possibility, but then people say 4" isn't enough, and that you want like 15" of vacuum? Not sure what to do, any tips, guides, links or products would be wonderful. Thanks!

 

Can I use something like this kit attached to an oil catch can? Or will the diaphragm in the pump just be damaged by the oil?

https://www.jegs.com/i/JEGS/555/63016/10002/-1

 

What rings are in the engine?

 

Paperwork says Sealed Power E-908K30.

 

In a wet sump application the max recommended crankcase vacuum is between 1 to 4" Hg with the average desired being 2-3" Hg of vacuum.
Using more vacuum in wet sump applications can create significant oil system issues, damage oil pump, dry the wrist pins, and other nasty oil system issues. Do some research on this.

Vacuum pumps and high vacuum situations are suited for DRY sump engines.

So to fully answer your question,
1. Yes you need a PCV system, completely FACTORY with respect to it's connections around the engine. For turbo engines you want a FACTORY turbo PCV setup like nissan/toyota uses.
2. The pcv valve I recommend is Toyota Supra twin turbo.
3. Use a short hose from the crankcase to run to the PCV valve and from there to the intake manifold. This will provide a suction on the crankcase during idle/cruise.
4. For boost situation, you need a tube that connects the pre-turbo (pre-compressor) tube to the other side of the crankcase, exactly like a nissan/toyota/subaru/etc factory engine. There should not be any catch can anywhere in the system because it will deteriorate the suction vacuum signal which only lasts for a brief instant in most turbo applications (especially manual trans cars which shift off throttle).

5. To set the exact pressure drop inside the crankcase is the most technical aspect of setting up. Between the pre-compressor and the crankcase, (#4 boost situation PCV) Toyota/Nissan uses a slight restrictor. The size of the restrictor depends on the max intake manifold vacuum signal and the PCV valve (which is why I select Supra PCV valve) orifice diameter.

What you want to do is run the pcv system intact without a restrictor FIRST, and measure the crankcase pressure using a 2-bar map sensor. Here is an example.


at 7:10-7:18 he begins discussing crankcase pressure measurement with the 2-bar map sensor.
That 2-bar sensor can relate your information and allow you to setup the pcv system properly.
What you want is to adjust the fresh air vent side (between crankase and pre-compressor) so that the crankcase is always under 2-3" Hg of vacuum which driving normally.
And then while you are in boost it should be the same, below 0psi for sure.
Sloppy mechanics is seeing pressure because he does not have the PCV system setup properly yet. He will get there one day but its still a good example to show how somebody can measure it and achieve a data-log of that pressure using a cheap sensor.