Most functional oil catch can
 

Have done a solid weeks research on catch can setups for the F20C with a focus on track work.

For now I am keen to keep the OEM setup ie

- valve cover breather to intake hose
- PCV to intake manifold

In light of above, I would like to go with a closed loop, non-vented setup which would require dual catch can for operation. This means that a catch can would sit like this;

- valve cover breather hose to catch can to intake hose
- pcv hose to catch can to intake manifold

For now it looks like Radium or Saikou Michi setup.

What has now provided me another road block in moving forward to adding an oil catch can setup in my car is what can is the most ideal and functional. In a catch can I would like one with:

- sight glass
- drain valve
- potential ability with a third bung already to add a breather filter in case I change setups in the future. *This would be ahrd to obtain so most likely rule out.

The purpose of this thread is to understand what all of the available "off-the-shelf" oil catch cans are available.
I am currently running a CAI and as a result even mounting the catch cans on the crossmember is a possibilty.

Cheers in advance,
Alex

I have tested three setups so far:

1. Closed Loop - Non-Vented - Single Oil Catch Can: PCV ---> 1lt Catch Can ---> Intake Manifold
2. Closed Loop - Non-Vented - Saikou Michi Dual Oil Catch Can: PCV ---> Catch Can ---> Intake Manifold & Valve Cover ---> Catch Can ---> Intake Hose
3. Open Loop - Vented - Single Oil Catch Can: PCV & Valve Cover ---> 1lt Catch Can ---> Breather Filter (the PCV valve is removed)

I was very fond of the closed loop setups, BUT the PCV hose "produces" about 500ml of oil in every track session. The Saikou Michi wasn't even big enough to cope with this amount of oil, and I removed it immediately. The closed loop setups were great for street driving, but in the track it was really annoying to drain the OCC after every session, so I moved to the open loop setup.

I have been running the Saikou Michi dual can setup on both my evo 8 and s2000 for years. But I have no track expearence with this and the s2000. Works fine for the street. And I have used it on the track with my evo8 with great results.

Thanks for providing me a real life experience example!

If you run hoses from PCV and Valve Cover to the 1Ltr catch can, wouldnt the oil still escape the PCV and into the catch can? I cannot see how the PCV will reduce oil loss with this setup unless you simply cap it off?

I have a Crawford AOS that I will be installing, but haven't gotten around to it. I have been running one on my STi for years and it's kept my intake, turbo, and intercooler bone dry and I haven't had to maintain the system. When I install, I will remove the PCV and then run both valve cover ports to the AOS ports, the port on the intake elbow will still draw vacuum and the AOS will drain into the oil pan.

The vacuum lines are the problem, especially the PCV vacuum line. If you remove the PCV Valve, run the hose from the PCV bung to the OCC, and the system is open (no vacuum line to the intake), there is no "suction" from the intake, and much less oil is accumulated in the OCC. If you leave the PCV Valve in place (or simple cap it), it will produce no oil at all, since it needs vacuum to operate.

For those that are seeing lots of oil go through the PCV, it may be an indicator that your front breather isn't flowing well enough. The PCV only activates off throttle and at WOT it is effectively closed. So at WOT when your blowby is greatest, enough of it is not evacuating out the front which builds up in the crankcase/valvecover and when you close throttle, the increase in vacuum in the intake manifold gulps all of that down.

So, let the front breathe. Watch the ID of whatever fitting you use. It may be significantly restricting flow.

But there may be nothing you can do to fully workaround the shitty AP1 engines.

Oil and water separators for air compressors work well for catch cans as well.

would this be the same oil causing some smoke on startup (after say a stint of mildly hard running down a curvy mountain road @ around 60 mph) and stopping after only approx 1/2 mile of slow (40 mph) driving? I've been having intermittent smoking on startup and after idling for a period of time (especially on an incline) on my MY 02 AP1. Not sure if I'm getting a PCV oil transfer issue or a valve seal blow by issue. I installed a K&N FIPK 2 kit a few days ago which has greatly diminished the smoking, yet I still notice a bit on startup. Especially when I've been parked on an incline. If a catch can setup would prevent me from blowing through a quart of oil every 3k miles it would be a lovely solution.

Needs to be baffled
Oil catch can needs to be lower than the pcv ports.

I went with moroso