Hi again,

Problem number 3

Previous owner had an oil catch can / coolant can fitted by J's Racing.
I noticed that a breather pipe from the top cover to the manifold has been removed and blanked off. Is this right / normal?
What happens to the oil in the catch can? Do I have to empty it periodically or what?
I dont know why exactly it is used ...

 

Don;t know about the install, but the catch can is used to catch oil that is pushed back into the valve cover before it goes back into the intake.
The idea being that it would get burned up but when you are pulling high G's you can push out oil that can foul the PCV and other intake components that aren't supposed to see oil.
Yup you have to empty it.

I learned based on a guy at the track with a WRX STI who had one that kept filling.

 

all the catch cans i have ever seen have the line going from the PCV to the intake manifold. I wonder if this is in anyway connected to your starting issue?

 

i have no idea .. maybe someone here has one and can elaborate ....

 

The catch can catches oil VAPORS - you will never have liquid oil running through those lines.

Think of the catch can as a filter in a vacuum. The line running into the can is coming from where you want to oil vapor NOT to be (in the crank case) and the other hose going into the catch can must be connected to a vacuum source.

The way you have it setup is fine. The intake, whether before or after the TB, will see plenty of vacuum when the TB blade is open, which is when you want to be sucking out the oily crankcase vapors.

The setup is a little different on a turbo car (must be pre-turbo).

I don't know if that catch can is any good. It needs to be baffled inside to get the oil to precipitate out of the vapors that are sucked from the crankcase. So, simply a can is not ideal. A can filled with steel wool separating the in/out ports is a start (assuming the steel wool is prevented from getting sucked into the intake), but still pretty ghetto.

 

the majority i have seen are like the pic below:

 

The above is the more correct way as it uses the PCV - there is no reason to block off the PCV valve as is done in the OP's setup.

 

that being said, the red hose going to the catch can is then connected to your intake

 

Is there a baffle in the Greddy catch can? If not, is it worth cutting open and installing?

I've also seen setups where the PCV and the opening on the front end of the valve cover are T'd together to the catch can and returned back to the manifold where the PCV would connect to. The other hose in front of the TB is then capped.

What are the benefits of that setup?

 

If there is none, prob not worth installing (unless you know how to weld Al).

I did some looking for catch cans - you can get the Moroso setup - which is baffled - but there is really no reason for the breather on top with our setup, so you'd need to cap that.

This is baffled pretty well (I called them up) and looks tasty: http://cgi.ebay.com/ebaymotors/05-10-MUSTA...sQ5fAccessories