I have an extra "cooler" from an EA81T oil cooler setup.

I think I might put it inline with the turbo and integrate it with the intercooler, for obvious reasons.

 

Would it be better to put it upstream of the turbo or downstream?

I'd definitely say downstream of the turbo. That way the oil cools off before entering back into the engine.

Might be REAL hard to do it downstream of the turbo. Outflow from the turbo tends to be an oil/air froth that needs to be quickly removed from the turbo... not really something that you can push through a cooler without another pump and a settling/separation container.

Mike, thanks anyway

Pat, that's awesome. Thanks. That explains why the drain passage underneath is so wide.

I took a good look at the turbo area today and it looks as if the oil feed line to the turbo comes straight from the oil pump. I'm certain that it's downstream of the stock oil cooler (which also comes straight off of the oil pump) because why wouldn't they give the turbo the coolest oil possible?

So, maybe there's no need to add an oil cooler right before the turbo.

 

But.. I need to change the oxygen sensor. I need to remove the turbo to do this, I'm pretty sure, and the header and downpipe gaskets need to be changed, and I might as well change the oil drain hose, and maybe change to a watercooled turbo while I'm at it. AND I'll be receiving my intercooler this week as well. So I'll have plenty of time to figure it out while I'm in there..