92 Black GT

Engine compression was pretty much the same as when I built the engine after break in. I did a leak down test on #1 and it was only 2% at 95 psi. Then my air compressor took a crap and that was the end of testing tonight. I tried my uncles compressor that he got used and it shot a fireball out of the plug that hit my leg. My leg is fine but obviously there is some issues with that compressor. That was my clue to call it a night.
Yikes! That sounds like a really fun surprise! Glad you are ok!
 
A little more investigation and I'm convinced that the new PCV system created enough back pressure on the crankcase blow by that it took an easier route which is the front seal of the turbo ( I had both the catch can with 40 micron filter + oil baffle, and the oil separator (essentially stranded stainless steel mesh creating back pressure). As far as I can tell the front seal of the turbo that I have is a floating ring. It has only so much tolerance for pressure. The oil inlet on this turbo is around 1/32". Tiny. It doesn't use much oil for ceramic ball bearing CHRA. Instead of the blow by going up into the head, and out the PCV system and back into the intake it said nope turbo oil drain tube is a way easier route then around the floating ring.

Solution: I will take off the 2nd catch can and leave just the oil air separator. I'll cap the intake port and put the same filter I used on the breather side. Upon reading online it is a good idea to have the hose leaving the PCV port on the valve cover going vertically up to the air oil separator. If any gas/steam oil cools while in route to the air separator the idea is that it drains back to the valve cover as liquid. I think long term I should weld a 10 or 12 an fitting onto the valve cover and run this to the 2nd catch can then put the filter on that. Then I would return the oil separator to the intake port. I will only do this if I don't like where my oil pressure is sitting at idle. I won't know until I try it for result. Now, I just need to clean everything down and try the first solution.

Real long term solution: replace rings and switch from a .013" top oil ring gap to a .011", and make the 2nd .013".
 
I cleaned everything down and routed the PCV port up hill to just the oil separator and then a large filter attaches just on the other side of the separator. No pcv valve and the intake port will be blocked. I was looking at where to put an additional valve cover port, and really it needs to go through the baffle in the valve cover. If this current setup is not enough welding the additional port will be a little bit challenging since it will need to get welded on the out side, and inside of the baffle. Another option might just be making the primary PCV port a 12 AN port.
 
I decided to make the primary PCV port a 12 AN fitting. I'll have to wait until next Monday to have my friend aluminum weld on the fitting. I have it prepped already. From the fitting I will go to a 12 AN 90 fitting with 12 AN hose all the way to the oil separator. I plan on tapping the oil separator inlet and outlet port from 1/4" npt to 1/2" npt. This should remove the blow by problem and the pressure on the turbo seals.
 
I ended up tapping the valve cover to 1/2" npt instead of welding on. I got all the fittings and hose in now, and I'm just waiting for the weekend and for a nasty cold to go away. I already prepped the spot to weld before realizing how easy it is to tap the valve cover to 1/2" NPT. I will just touch up the valve cover next to the fitting out with the same color enamel. The fittings go from 1/2" npt to 12 AN, immediately to a 90 degree 12 AN, 12 AN hose to 12AN to 1/2 NPT into the oil separator. I tapped and threaded both ends of the oil separator from 3/8" npt to 1/2" NPT. The Filter ends up in the pocket behind the driverside strut mount matching the breather filter on the other side.
 
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