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Discussion Starter · #1 ·
The engine has Tomei sump; how exactly do I know what level the oil should be at? The dipstick, of course, has it's L and H but I assume that the tomei sump can hold more oil.

Basically, oil is coming out of the dipstick feed but, having complete a compression test, everything seems normal with all cylinders 1psi of each other at 170psi average. I'm wondering whether I've got too much oil in the car which is causing the crankcase pressure.
 

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Discussion Starter · #3 ·
The seller just called it a tomei sump but if I'm just using the wrong terminology and you recognise a tomei sump as a tomei baffle then yes.
 

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The seller just called it a tomei sump but if I'm just using the wrong terminology and you recognise a tomei sump as a tomei baffle then yes.
Does the sump look stock from underneath? If it is then it's just a Tomei baffle that is fitted. Fill the engine up with 5L of engine oil :)
 

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My view is that regardless of what sump you have or baffle you should use the standard dipstick markers to determine if it is full. If you have a larger sump then you will need to put more oil in in order to reach the max line on you standard dipstick.
Hope that helps.
 

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Discussion Starter · #6 ·
Ah, yeah, that is a very good point! Physics fail award goes to me!

So I'm beginning to think that the cause of the additional pressure is because I've been told to fill it a lot further than the H by the seller.
 

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Maybe but filling up higher that the max will cause the oil to have bubbles in it due to churn from the big ends dipping in the oil. That can cause major oil pressure issues.
 

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Discussion Starter · #8 ·
My oil pressure gauge seems to report quite normal results, doesn't jump around a lot. Typical increase as you get higher in the RPM and much higher pressure on startup etc.
 

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I'm sure it's fine but I would get the level down to normal if I was you. I would imagine that bubbles in the oil could accumulate over time.
They did put the max level there for a good reason :)
 

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Discussion Starter · #10 ·
Yeah, you're spot on.. I'm just curious as to why the seller would specify that the oil should go to the notch and not the 'H'. Especially since he built the engine; it's a fully forged engine with a N1 24U block. It's way too quick for me but I run it at lower boost and drive it like an old woman!
 

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I've been told the same think, the reason is to help prevent oil starvation if you are having a breathing issue and the oil isn't returning to the sump quick enough. It's really a way to hide a real problem.
I've been down this road and ended up putting proper oil breathers into the sump so that the bottom end can breath well, which is what most other engines have. The Rb26 is badly designed with regards to breathing in my opinion.
 

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Discussion Starter · #12 ·
Oh right, eek.

So the PCV valve has a venturi connection into the exhaust which should be releasing some of the pressure.

For now, is it best to keep the oil a little fuller then in this case?
 

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Oh right, eek.

So the PCV valve has a venturi connection into the exhaust which should be releasing some of the pressure.

For now, is it best to keep the oil a little fuller then in this case?
When I took mine to MGT they said 5L of oil is what it needs.
 

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Are you actually having oil pressure issues?
I assume you have not got a catch tank fitted, that might help with breathing.
I'm not sure actually how much help it would be to overfill the oil.
I only knew that I had a problem because I was hitting oil pressure trips on my syvecs and then did some data logging. I wouldn't have been able to tell with the standard gauge while driving.
 

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Discussion Starter · #15 ·
I do have a catch can but it sits on the dip stick connection as a breather.

The venturi PCV connection to the exhaust, naughtily just spits everything out there.

I'm not sure the Apexi ECU can log oil pressure
 

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So I would say that if you don't think you have an oil pressure issue then leave as standard level.
If you think that there is a problem then I would fit a pressure gauge that records the max and min pressure so you can check, not sure about what the apexi is capable of.
 

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Discussion Starter · #17 ·
Alright, well thanks for your help that does clear some things up.

The main reason I'm asking is because there's pressure in the crank case that is sending oil up the dipstick feed on high boost. Since the compression test doesn't indicate any leaks (No blue smoke either), I can only assume that there is either too much oil or the PCV system with the venturi port to exhaust is not working.
 
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