[chrisp]

Originally Posted by JLMounce

That's correct, it's functioning like a PCV valve where you're moving pressure from the crank case to the intake, until there is a surplus of pressure and at that point the draft can will vent the pressure.

The breather has some foam in it to keep oil contained, but is otherwise open.

I did not have to change anything in my tune when I made this change and have not witnessed any changes in my reported AFR's or my short/long term learn trims.

The big thing this is doing for me is providing ventilation operation during high vacuum/high rpm situations where a stock type PCV valve would otherwise be closed.

Any increase in engine vacuum @ idle after the upgrade ?

[JLMounce]

Originally Posted by chrisp

Any increase in engine vacuum @ idle after the upgrade ?

Not from the change to the draft setup. What helped me the most in that regard is letting the EFI control the timing. Gained a full 2” of vacuum at idle with the ability to command up to 24* of advance at idle. The system idle stabilizes advance between 18-23 degrees usually.