Best Catch Can/ Oil Seperator Set-ups

[sqc151]

i have the grimmspeed seperator for my 05 LGT.

$300 GrimmSpeed Air/Oil Separator

http://www.grimmspeed.com/catalog/produ ... cts_id=191

[James614]

Does it work as well as it's price would suggest?

[sqc151]

mainly got it so i dont have to empty a can all the time. this puts the oil right back in the car so i never run low either. i check often anyway, but with over 500whp u wanna always make sure u have oil...

[Legacy777]

I will caution everyone that there are correct ways and wrong ways to hook up a catch can or oil separator. I will encourage you to read over how the stock system is designed to work.

http://www.main.experiencetherave.com/s ... system.jpg
http://www.main.experiencetherave.com/s ... _turbo.pdf

I read the comment on the provo separator. It talks about only being hooked up to the heads. Well the heads don't need any separation. The ports on the heads draw fresh air into the motor, not out. The main port on the back of the engine block is the one that all the oil vapor comes out. The way the PCV system works is that under low throttle (high vacuum) situations, the oil vapor is pulled in primarily through the PCV valve. Under higher throttle (low vacuum) situations, the oil vapor is pulled in through BOTH the PCV valve AND intake piping.

If you only have the PCV system going to the PCV valve, OR just the intake piping, you could be letting the crankcase build up excess pressure. They do make catch cans with vents/filters to atmosphere. These would allow for excess venting during high throttle situations, but make the PCV system an open system vs. the stock closed loop setup. If you are using a MAP based engine management, that's not too big a deal. With a MAF based engine management system I would say it's preferred to have a closed loop setup.

sqc151, how is your grimmspeed setup?

[kimokalihi]

So does the grimmspeed separator plumb up properly to allow pressure to vent off the way it was designed to by subaru?

[Legacy777]

Yeah it can if you hook it up properly. You'd want to run the line from the vent pipe on the block to the AOS, then run one of the outlet lines to the PCV valve, and the other outlet line to the appropriate spot on the intake tube/piping before the turbo.

[kimokalihi]

It seems like it could still be passing oil vapor through since the place it comes in from the crank case under that filler cap piece is the same place it goes back out to the intake. I guess it has to travel around inside the ring first but still.

[Legacy777]

In theory the difference is that fresh air supposed to be supplied to the heads and exhaust gasses are to flow from the main crankcase to the catch can/AOS.

Personally, I'd probably opt for something else, but that's me.

[kimokalihi]

Have you seen this company? They build you a catch can or dual can setup to your specifications.

http://saikoumichi.com/

[Legacy777]

No I haven't seen them before, but a quick look at their site would seem to indicate they make a good product and know what they're talking about. I was glad to see this:

http://www.saikoumichi.com/OCC_explanation.htm

[kimokalihi]

Yeah looks pretty well done. Beats buying a cheap off the shelf one size fits all cookie cutter product and its affordable enough as well considering the assumed quality and made to order cutstom work.