This post will refer to the following variations of oil catch can setups.



*Note* I have searched and read many other threads and posts on this subject, but still don't have a clear answer to my question. In fact, the main Oil Catch Can thread ended with me asking is exact question 8 months ago, but now I am ready to install an oil catch system so I'm bringing this topic back up in hopes of getting some feedback this time.

1 - Stock PCV system, oil catch off the crank case breather.
2 - Oil catch in line with PCV, simple filter on crank case breather.
3 - Both sources sent to oil catch with breather, no PCV.
4 - Both sources sent to oil catch in line with PCV and vacuum from intake manifold.

Alright, it seems as though from my reading that many of us have done 1, 2, and 3. However I would assume that with 1, most oil and grime would still do through the PCV since it has a vacuum source and the oil catch does not. 2 seems fully functional. As it has been described elsewhere, I don't know how effective 3 would be as the filter on top of the oil catch can does not necessarily draw the oil and grime out of the crank case.

Thus, I would bet that setup 4 is the most beneficial in all respects. It keeps the PCV system in tact and just catches the oil as it passes through, and no vacuum pressure is lost from a breather filter keeping a healthy flow of harmful gases and oil out of the crank case.



Do you agree with that logic and think the 4th setup will work the best? Is there anything wrong with it? Any other input regarding any of those variations shown above?

Thanks! BTW, I will be turboed within a week or two - running 8 psi for a few months then moving on to ~20 when I can afford the rest of my fuel system and MSnS if that affects the decision.

I have been pondering a functional oil catch can setup for quite some time. It seems to me that number two would do just the trick. As for 4, how is the crank case able to drawn in air for ventilation?

Hah, well I guess I didn't even think about how fresh air would get in. In that case yes #2 would be the best bet.

I agree that number two is the best system. Like you said, just be sure to keep the stock PCV valve (or an upgraded check valve).

Here is my new setup. It resembles number 2. I just used a mini air compressor filter as the catch can. The PCV system is still in use. As you can see also, I used a mini filter for ventilation.

nice! my catch can isn't small enough to fit there so I'll need to find a good location, but the same setup. I'm thinking either where the stock air box was, or preferably where the cruise control stuff is if I remove it.

I put my catch can only on the breather valve. I had a bad problem with oil getting shot through that filter on hard right turns and the oil would cover the motor.

i have used number 3 method for a long time .

i use a modified #4, line vac is provided by the turbo intake.
two lines come off the VC and to the catch can.
then a line goes from the can to a spot just behind the filter on the intake pipe to the turbo. that way its scavanging both on and off boost. (as opposed to a std pcv that only sees vac off boost)