Gen III PCV system

[Zubik]

This is more of an informative post. This stems from me changing valve covers. I was changing my accessory belt and saw descent amount of oil in the intake/throttle area and this led me to this rabbit hole.

Original PCV system routing:
-passenger side vent, top firewall side. This vent has a reducer ~7/64"/2.78mm in size. There's a plastic/rubber line that runs under the plenum to a port behind the throttle body, on the under side. This is the PCV system for the car. There are baffles and this foam stuff between the valve cover and the port, so oil would not get slung up it. The car always draws some fumes/oil vapor that gets burned up by the engine. There is no check valve. Here's a shot of the original restrictor in the valve cover port.
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-driver side vent, top firewall side. This is a completely open port w/out restriction. There's plastic/rubber line that runs under plenum to before the throttle body and plugs in on the driver's side of the intake box neck. This is just a breather to feed air when need be.

My PCV system routing:
- placed a Dough Shelby catch can on the passenger/restricted side. Everything else is routed same.

So the issue came about me changing valve covers. These are same gen, but did not have any restrictor in any of the ports. I did not realize this. The car puffed some oil on start up, sometimes, and I was searching for a reason and finally found it by taking my intake box off. Right away I thought of the PCV system and led to this post.

My solution to this was to make a restrictor myself. The catch can lines are 5/8" and the port takes a 1/2" line. I had a hose reducer right at the passenger side valve cover port. What I ended up doing is designing a new reducer w/restrictor built in and 3D printing it.

Here's some pics of the design and the print:
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1st impressions was that the car idles better. The oil issue at the throttle body has been resolved.

This is clear FormLabs resin. On the old valve covers I printed another reducer w/a 90 degree bend in it. I ran it for ~two years and it held up fine. Don't judge the old one. As one can see my design skills improved a bit =P
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