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Discussion Starter #1
although my car is hardly lacking for wet sump oil system mods, I did not do a head drain, due to my questioning about where to dump the drain, and I don't quite buy into plugging it into the oilpan - oil could just as easily flow backwards into the hose (granted, not all the way into the head). Not a problem if you mount the drain at the front of the pan, but cars stop as well as start (unless we're talking about a drag setup) which pushes oil towards the front.

Anyways, a long head drain hose run from the back of the head to the front of the engine, I'd want a more downward pointing angle on the drain hose.

So it has just occurred to me, why not empty into the turbo oil drains? True, the turbo drains are significantly smaller than a -12AN hose, but a Y-adaptor could be quickly and easily fabricated.

My Nismo oil separator empties into the rear turbo oil drain. Unless someone can explain why dumping a head drain into a turbo oil drain (front or rear) would make the whole head drain useless, I think I'll do that next time I pull my head (probably next summer I'll take the head off to fortify the valvetrain for higher revs, and do the head studs while I'm at it. Engine-in job).

Am I missing something big here? Other than going against convention and the Australian standard way of doing head drains?
 

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the oil from the head isnt pressureised so it need to be returned under the oil level or it wont actually go anywhere
 

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the oil from the head isnt pressureised so it need to be returned under the oil level or it wont actually go anywhere
That's just plain wrong. Unless crankcase pressure (blow by) was so bad that a pressure differential existed at all times with the sump being higher pressure than the cam boxes oil will drain down through gravity. Doesn't matter whether the sump drain is above or below the sump oil level.
 

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Wait. Am I right in thinking that you're under the impression that oil will magically work its way from the sump up to the head using nothing other than accelerating/braking hard?? You would need to be doing wheelie starts and have brakes the diameter of London to be getting anywhere near having issues of that sort......

Personally I would plug the drain in somewhere above the oil level if for no other reason than if I wanted to remove it for some reason I wouldnt have lots of the black stuff over the floor of my lovely garage!!

Methinks your doing that over-analysing thing again Toby.....back to the therapist :chuckle:

TT
 

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Discussion Starter #6
no, not that far gone mate :) but I do question putting the return under oil level, because the oil dripping from the head is by gravity only, and not in dramatic amounts.

Think I'll Y-pipe it into the turbo drain - those were designed to take low-pressure oil anyways.
 

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Isnt there a thread on this already. One bloke came on and said it isnt a oil drain as such but a pressure relief. Your venting your crankcase to your head and your head to your catch can. This in turn allows your oil galleries to do their job in a much more efficient fashion.
So would that mean venting your crankcase to you catch can be the same thing? I think Dirt garage does some funky stuff from memory.
 
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