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Old 06-09-2015, 01:42 PM   #1
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So had oil coming out of the turbo exhaust and after a compression test found 3 and 4 are at 50psi. My oil feed runs from the cam feed on drivers side behind the head. Haven't pulled the motor yet but seeing if this location is to why this happened or if it is a result of 12 years of nitrous. Would think that all the oiling comes from the crank feed but asking the professionals. Thanks
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Old 06-09-2015, 02:00 PM   #2
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Quote:
Originally Posted by Rion View Post
So had oil coming out of the turbo exhaust and after a compression test found 3 and 4 are at 50psi. My oil feed runs from the cam feed on drivers side behind the head. Haven't pulled the motor yet but seeing if this location is to why this happened or if it is a result of 12 years of nitrous. Would think that all the oiling comes from the crank feed but asking the professionals. Thanks
ummm, wat?
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Old 06-09-2015, 05:02 PM   #3
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Yeah, some people think taking oil pressure from the head is bad. There is supposedly a restriction between the crank and valvetrain, you don't pull oil post restriction.

No, that will not cause rings/valves to burn. What a dumb question.
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Old 06-09-2015, 07:38 PM   #4
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Didn't realize there was a restriction there. Didn't really want to "T" off the sending unit just being other side of the block and have heard of breaking issues; this just seemed cleaner appearing and liked the accessibility.
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Old 06-09-2015, 07:45 PM   #5
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David did a study on using that port, and has had no issues I'm aware whilst using it himself.
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Old 06-09-2015, 08:02 PM   #6
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That's nice to know. Haven't got to drive the car much but did take it to one autocross so when I pull it I'm going to check the cam for wear to make sure it was getting enough oil. There was definitely enough pressure out if it; started with a -04 line and when the turbo started leaking I changed to a -03 and put a new turbo on which leaked. That's when I noticed how much pressure was coming from my catch can. After finding the compression numbers came to the conclusion there was enough crank case pressure it was pushing the oil coming from the return back into the turbo
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Old 06-09-2015, 09:09 PM   #7
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I'm pretty sure nitrodann uses that head port, almost exclusively. I want a 94-95.5/whatever block for this reason.

If the lifters weren't making a ton of noise I doubt you robbed enough oil to damage the cam.
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Old 06-09-2015, 09:30 PM   #8
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I saw that the port was supposedly only that year when I was researching so was surprised when my 01 had it. Everything sounded good when it ran just didn't get to run too long. A hard day at the autocross lost about half a quart. Thought maybe the bushings being a used turbo so just went for it and bought a new one. After 2 starts it was toast. Seems like quite a bit of endplay (around .010" to .015") but basically the whole blowby problem got worst in a matter of 5 starts that's when I did the compression test
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