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Discussion Starter · #1 ·
SO, I have both ports on the front VC and the one from the rear VC all tee'd together and running to the catch can. I have a check valve between the catch can and the manifold.

When Im in vacuum everything runs great. No oil blow by in the turbo at all.

When I go to boost, the check valve closes and I get just a small amount of blow by. This is due to the check valve closing and the oil fumes / crankcase pressure having no where to go. Essentially capping all the PCV off.

The smoking I have now is nowhere near close to when I had the manifold hooked up to the front VC, so I do know that the check valve is good, and that it is not directly pressurizing the crankcase from the turbo pressure.




Question is, how do I vent the pressure from the VC's while I am in boost? Do i need to put a little poppet valve to vent to atmosphere while in boost?
 

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Your talking about the two larger lines at the very front of the front VC and the verry back of the rear VC not the PCV line at the top of the front VC right?


If those see boost it will travel to the crank case and unseat the rings.

If they arnt allready plumb them in in front of the turbo inlet or just vent to atmos.

Theres a chance that if enough oil gets through and is injested by the motor it can increase the motors tendency to knock. Oil has a really low octane rating.
 

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Discussion Starter · #3 · (Edited)
I am not presurizing the crank case, that is what the check valve is there for.

I could also plumb it in at the turbo inlet like you said, but I have no piping there. :(

I need the vacuum to pull the fumes through the catch can. Which is working 100% no problems at all. Its when the check valve closes that the fumes have nowhere to go. I suppose I could do just like you said and vent it to atmosphere with another check valve so that it can release gas, but once I drop back to vacuum that second check valve will close.

Only problem with that then is the oil fumes will build up in the line and eventually drip under the car. I know they will not allow that at the track for sure. For everyday driving its a semi-viable solution.
 

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Discussion Starter · #5 ·
Nope its not. I dont have any pipe/filter on right now because where I had the filter located hit the drag radials...

I need to buy a smaller filter, and I will plumb it into the turbo inlet like you said. Is that how yours is hooked up king?
 
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