Catch cans: what are you running?

[Dezoris]

The hoses needed:
The intake manifold barb is 1/2"
PCV Valve Barb is 11/32"

[soros151]

Watching

[MANDALAY]

Sometimes its worth to see what other cars have installed/designed.

This is a great design , absolutely a work of art, all billet and blends in like an OEM part.

Works which is the key and is cheap at $179. One of the highest upgrade parts in the BMW scene

http://www.google.com.au/url?sa=t&rc...DeboWslkVSBpCA

[Dezoris]

Originally Posted by MANDALAY

Sometimes its worth to see what other cars have installed/designed.

This is a great design , absolutely a work of art, all billet and blends in like an OEM part.

Works which is the key and is cheap at $179. One of the highest upgrade parts in the BMW scene

http://www.google.com.au/url?sa=t&rc...DeboWslkVSBpCA

Nice piece, too bad it does not have interchangeable barb sizes.

[Ingen]

Originally Posted by Dezoris

Nice piece, too bad it does not have interchangeable barb sizes.

how off is it?

[Dezoris]

Originally Posted by Ingen

how off is it?

That can is: 0.62" OD

The OEM FR-S BRZ Intake Manifold Barb is .50" and the PCV Valve is .425"

[Turdinator]

Can someone explain to me how the PVC system works on the FA20? My knowledge of these systems is based on pre 80s engines and is clearly floored as looking at the Crawford oil air separator it should create a route for air to bypass the throttle which it clearly doesn't in practice.

[Ingen]

Originally Posted by Dezoris

That can is: 0.62" OD

The OEM FR-S BRZ Intake Manifold Barb is .50" and the PCV Valve is .425"

Huh. Well what's to stop a guy from getting a bar of hex aluminum off McMaster and spinning out a couple of hose-size-adapters? It doesn't seem too difficult, provided you have access to a lathe, which I will admittedly have to haggle over slightly.

But it's a gorgeous can, MUCH cheaper than the other options I have seen, and appears to be quality.

Tell me why this idea is bad?

[Dave-ROR]

Originally Posted by Turdinator

Can someone explain to me how the PVC system works on the FA20? My knowledge of these systems is based on pre 80s engines and is clearly floored as looking at the Crawford oil air separator it should create a route for air to bypass the throttle which it clearly doesn't in practice.

It goes from the PCV valve to the intake manifold. There's another port (not PCV valve though) going to the intake tube that sees less blowby on a NA engine.

[Dave-ROR]

Originally Posted by Ingen

Huh. Well what's to stop a guy from getting a bar of hex aluminum off McMaster and spinning out a couple of hose-size-adapters? It doesn't seem too difficult, provided you have access to a lathe, which I will admittedly have to haggle over slightly.

But it's a gorgeous can, MUCH cheaper than the other options I have seen, and appears to be quality.

Tell me why this idea is bad?

He's not saying it's bad, just that it's going to take more work/parts to make it work.

[Dezoris]

Originally Posted by Turdinator

Can someone explain to me how the PVC system works on the FA20? My knowledge of these systems is based on pre 80s engines and is clearly floored as looking at the Crawford oil air separator it should create a route for air to bypass the throttle which it clearly doesn't in practice.

I summarized a Toyota SAE Article about PCV Systems:

SAE Toyota Journal About the Importance of PCV Systems in Modern Engines Summarized by Dezoris:

What does the PCV System Actually Do?

The PCV system is designed to recycle engine blow by gasses back into the intake for emissions purposes.

However to do so it requires a variable PCV valve because the amount of blow by gas coming out of the engine down the PCV hose is not always equal to the amount of vacuum at the intake manifold.

So the PCV valve is opened and closed based on the amount of vacuum at the intake manifold and the amount of blow by gasses being vented. This helps to equalize the vacuum and gas pressure to insure smoother engine operation. The air to fuel ration and the tuning for that system takes into account PCV vacuum and air flow.

1. Full Throttle and high RPM = Lower Intake Manifold Vacuum, High Engine Blow By.
In this condition the PCV Valve is forced full open. If there is too much blow by then the breather hose will also be used to vent into the intake hose. This will only occur under high load situations.

2. Lower Throttle, Cruising = Moderate Intake Manifold Pressure, Lower Blow By.
In this condition PCV Valve is half open

3. Idle or De-Acceleration = High Intake Manifold Pressure, very low blow by.
In this condition the PCV valve is virtually closed.

Side Effects and how to Test for Issues:

PCV valve and PCV Hose:

PCV Valve is engine specific to engine tuning, if you use the wrong valve or it becomes clogged the air/fuel ratio computation tends to run rich. Rough Idle, stalling or performance issues could also occur.

Testing for blockage or faulty PCV Valve:

First you want to plug in your OBDII scanner and monitor engine RPM.
Once the car is fully warmed up or your coolant reaches 170 Degrees or higher, clamp off your PCV tube from the PCV valve to the intake manifold. Once blocked engine RPM should drop 50-100RPM.
If it does not you may have a damaged PCV hose or bad PCV valve or the system is clogged.

In this case you may see issues with rough idle or some drivability issues. The PCV line is under vacuum, not the breather hose.
A plugged PCV line will cause higher oil consumption in the crank case.

Breather Hose:
Its primary design is to vent excess blow by that the PCV valve and hose can't pass. Usually only under high load.
If the breather hose is clogged or blocked it will cause higher pressure inside the crank case which can cause higher oil consumption and or more unburned fuel which can contaminate the oil. However a leak in the breather hose wont generally cause any issues.

Used Oil Analysis:
Sending out used oil will help to show if there is a higher level of fuel in the oil which could also track back to a faulty PCV system.

Oil in Intake Tube:
Usually is caused by a faulty PCV valve stuck open restricted PCV hose which will cause more oil in the breather line.

[Dezoris]

Originally Posted by Dave-ROR

He's not saying it's bad, just that it's going to take more work/parts to make it work.

Yes, if you like the can and have the tools needed to modify or adapt the barbs on the BMW can go for it.

[Ingen]

Originally Posted by Dezoris

Yes, if you like the can and have the tools needed to modify or adapt the barbs on the BMW can go for it.

Sweet, sold

This project will be fun. And it'll go nicely (if unrelated) to my DIY armrest that I am going to be working on soon. Eventually.... when I get around to it... yeahhhh...

[Razz]

Your best off putting a filter at the oil end and capping off the air intake side.

No need for catch can.