3SGTE Gen2 crank venting

[motorheadsw20]

Hey Guys,

I was mucking around with catch cans and breathers - and I was wondering if on the Gen2 the crank is vented through the oil galleys up to the top of the valve cover (where the vent is) or was there another mechanism/way of venting the crank?

I don't have the factory oil pan any more - so wouldn't have a clue if there was some breather hose there in the past.


I was also contemplating that one can use a T on the turbo oil drain hose connected to a catch can as a breather - and while I know this goes against the flow of the oil it's a fairly chunky diameter hose - so technically should work but I don't know if anyone's tried it (I found out the Porsche 930's use this approach for crank venting)

Any advice / comments / info would be most welcome

[GDII]

You mean the crank case as in below the head? There are large oil drains in the block to head where the air can escape up to the valve cover. Changing the sump does nothing to change this system. Remember, the 3SGE has no turbo drain plus the air can't go up the turbo drain anyway.

Just vent the 2 (or more) ports on the valve cover to the catch can. You can drain the catch can to the sump if you are able to. It's now called an oil air separator as it no longer catches anything.

[motorheadsw20]

Yep meant the crankcase / oil pan for venting.

Where this came from was that since I'm planning to run 20+ PSI the tuner was asking how the valve cover is getting vented (which will be 2x 12mm ports) as well as how the oil pan was getting vented.

I found some guys do an extra port on the oil pan (https://www.mr2oc.com/threads/catch-can ... an.417064/) - but I'm wasn't too keen on doing that.

This kind of summaries the theory

https://www.enginebasics.com/Engine%20B ... nting.html
https://dsportmag.com/the-tech/quick-te ... re-part-1/

But for the sake of understanding this in relation to the 3SGTE Gen2 I might use the oil temp port I have on the oil pan and put on a hose fitting and use the boost gauge to actually measure what kind of pressures we're talking about


There is indeed large oil drains in the block as noted (thanks for the tip - it made me go an actually look ) so if someone needs a reference to those they are outlined in the pics below.

Imho that nullifies a need for external oil pan venting and venting from the valve cover should be sufficient.

[GDII]

I think that's more work than needed. 20psi isn't huge, venting the valve cover will be fine for that.