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Well fuck, I wish that bit of info was made a bit more loud.

Try a valvecover with a baffle.


No baffle plate means any and all oil that gets flung off the camshaft is going straight into the vent.


Not so sure it would help with vacuum, but it sure could be a source of the oil chugging.
 

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Discussion Starter · #122 ·
Well fuck, I wish that bit of info was made a bit more loud.

Try a valvecover with a baffle.


No baffle plate means any and all oil that gets flung off the camshaft is going straight into the vent.


Not so sure it would help with vacuum, but it sure could be a source of the oil chugging.
It did it when the baffle was still in place aswell. And the valve cover vents to the catch can that has a baffle in place so I doubt it would be chugging oil. Ill check my intake piping for any oil residue
 

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Hopefully something shows itself.

Just because it is a high comp build, doesnt mean it should be straying TOO far away from OEM stuff.

I would be curious about using an arduino and a couple MAP sensors, and reading vacuum/pressure off various points of the engine. Crankcase, valvecover, intake before throttle, etc..


Curious indeed!
 

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Discussion Starter · #124 ·
Well I reverted the PCV system back to the black box +pcv valve to the intake and just the catch can from vc to intake tube. It still smokes. At this point all I can think of is the car being to restricted air wise. I do have a bumper mounted CAI coming in which should increase airflow a bit. If that doesnt work I'm totally out of ideas. Ill give the arduino thing a shot since I have a couple laying about. Just need some map sensors. Also another pesky valvecover oil leak popped up. It just will not seal no matter how many covers and cleaning methods I tried...

Well fuck, I wish that bit of info was made a bit more loud.

Try a valvecover with a baffle.


No baffle plate means any and all oil that gets flung off the camshaft is going straight into the vent.


Not so sure it would help with vacuum, but it sure could be a source of the oil chugging.
The catch can barely had anything in it. Mostly water from condensation with oil mixed. Mhm milkshake
 

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Frustrating.

Hope you find something out!
 

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Discussion Starter · #126 ·
Right yet another update with more data.

Hooked the vacuum gauge up to the intake manifold and went for a drive.
Cold vacuum is around 18inHg but improves to about 20-21inHg at idle when the car warms up
Cruising at 80KM/H in 5th gear (~2400RPM) gives me around 14inHg of vacuum
Cruising at 100KM/H in 5th gear (3000RPM) gives me around 16-17inHg of vacuum.
At any given RPM above 4000, when I take my foot of the gas and let the car engine brake the vacuum shoots to 25-26inHg and stays pinned there untill its below 4000RPM again, indicating its pulling much more vacuum. I think its the gauge maxing out on me.
One thing to note is that with my new Injen Cold Air Intake (bumper mounted filter) it seems to smoke less than it did. I am extremely sure this is a vacuum issue now.

I'm really wondering what I could do to reduce the high RPM vacuum. I'm thinking a high flow PCV valve could do the trick? Or some sort of check valve that opens at a certain pressure difference. I'm not sure yet on what to do. Any tips would be great, maybe some suggestions for sturdy PCV valves designed for modified engines. I'm also gonna invest in some stronger vacuum hoses to and from the intake. I have a feeling that these current ones might be collapsing under the high vacuum.
 

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At any given RPM above 4000, when I take my foot of the gas and let the car engine brake the vacuum shoots to 25-26inHg and stays pinned there untill its below 4000RPM again, indicating its pulling much more vacuum. I think its the gauge maxing out on me.
This is normal, even on engines that do not smoke.

Remember, engines are just air pumps. Heck, many vacuum pumps are simply reciprocating pistons in a cylinder.

You cant really control the amount of vacuum our engines make, without other significant modifications. Almost all throttle cable operated engines that slam the throttle plate shut on lift off, while the internals are still reciprocating and valvetrain is in time, will pull intense vacuum. You cant really do anything about this. They make great vacuum pumps lol, that is their nature.

In any case, the engine components themselves are designed for this. When everything is right, they'll seal and prevent oil from entering the intake tract or the combustion chamber.
  • Think of the way valve stem seals are shaped. When the seals are in good condition and the valve guide is in control of the stem movement, when the valve seal is exposed to vacuum from underneath it literally squeezes the seal harder against the valve stem.
  • The piston rings when in good shape, oriented correctly, as well as the cylinder conditions themselves, are designed to scrape oil downward off the cylinder walls back down towards the pan, so only the most miniscule amount is exposed to the combustion chamber at any given time. Even at the ring end gaps, when the rings are clocked correctly, they try to create an oil movement restriction for any oil that might be built up or trying to move between the ringlands.
Again, the amount of oil normally exposed to the combustion chamber is actually an OE design constraint, where the parts involved that the OE has chosen to use in the engine design make their oil consumption target possible. It is unavoidable to remove all oil exposed to the combustion chamber, but the amount present when things are working correctly is so unbelieveably small, its burnt constituants with a hot exhaust system on lift off type conditions are almost undetectable on a 5 gas, and certainly not visible out the tail pipe.

Since you've increased compression ratio, technically you've also increased the amount of vacuum the engine is able to create, since you're trying to pull a vacuum against a smaller overall initial space. The result is a deeper vacuum on average. BUT again, so long as things are working properly mechanically, the engine components are designed to handle in cylinder and intake vacuum conditions, while controlling oil consumption.

Many others have built high compression engines that don't smoke, I have a feeling whatever is causing your issue is fundamental in nature, and like all complicated diagnostic sessions, a simple problem (that may or may not be easy to get to) will likely be your root cause.

Diagnosing oil burning/consumption issues from across the pond is a difficult affair! I truly hope you get this figured out, but without any of us physically coming over and putting hands on things, I dont know what else we could suggest to try remotely!

Germany just needs to take over like a little bit of Canada, so we can be neighbors lol. We'll come over then and give you a hand!
 

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Discussion Starter · #128 · (Edited)
This is normal, even on engines that do not smoke.

Remember, engines are just air pumps. Heck, many vacuum pumps are simply reciprocating pistons in a cylinder.

You cant really control the amount of vacuum our engines make, without other significant modifications. Almost all throttle cable operated engines that slam the throttle plate shut on lift off, while the internals are still reciprocating and valvetrain is in time, will pull intense vacuum. You cant really do anything about this. They make great vacuum pumps lol, that is their nature.

In any case, the engine components themselves are designed for this. When everything is right, they'll seal and prevent oil from entering the intake tract or the combustion chamber.
  • Think of the way valve stem seals are shaped. When the seals are in good condition and the valve guide is in control of the stem movement, when the valve seal is exposed to vacuum from underneath it literally squeezes the seal harder against the valve stem.
  • The piston rings when in good shape, oriented correctly, as well as the cylinder conditions themselves, are designed to scrape oil downward off the cylinder walls back down towards the pan, so only the most miniscule amount is exposed to the combustion chamber at any given time. Even at the ring end gaps, when the rings are clocked correctly, they try to create an oil movement restriction for any oil that might be built up or trying to move between the ringlands.
Again, the amount of oil normally exposed to the combustion chamber is actually an OE design constraint, where the parts involved that the OE has chosen to use in the engine design make their oil consumption target possible. It is unavoidable to remove all oil exposed to the combustion chamber, but the amount present when things are working correctly is so unbelieveably small, its burnt constituants with a hot exhaust system on lift off type conditions are almost undetectable on a 5 gas, and certainly not visible out the tail pipe.

Since you've increased compression ratio, technically you've also increased the amount of vacuum the engine is able to create, since you're trying to pull a vacuum against a smaller overall initial space. The result is a deeper vacuum on average. BUT again, so long as things are working properly mechanically, the engine components are designed to handle in cylinder and intake vacuum conditions, while controlling oil consumption.

Many others have built high compression engines that don't smoke, I have a feeling whatever is causing your issue is fundamental in nature, and like all complicated diagnostic sessions, a simple problem (that may or may not be easy to get to) will likely be your root cause.

Diagnosing oil burning/consumption issues from across the pond is a difficult affair! I truly hope you get this figured out, but without any of us physically coming over and putting hands on things, I dont know what else we could suggest to try remotely!

Germany just needs to take over like a little bit of Canada, so we can be neighbors lol. We'll come over then and give you a hand!

Haha yeah that would be handy. And I do believe its probably something very simple that is causing the issue. From what I've tested everytime I mess around with the vacuum I see better results, hence why my guess is that that would be my issue. I'll still replace the PCV valve since that is original (still working but can't hurt, basically in the process of elimination now) and the vacuum hoses with stronger ones and see what happens...

As mentioned by oldcivicjoe that the PVC valve could close under too much vacuum, could that also be an issue, if so that would mean that my pcv valve might not be up to the task of this high of compression. ~13:1 is what I'm running so its pretty hefty. Note that this is just guesswork as I'm going to try even the weirdest of solutions to get it to stop smoking so bad
 
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