Mike Murcia

Should the AOS be drilled if you're not running a catch can? I don't have oil sitting in the hose coming from the separator to the j-boot, so I don't think I need a catch can. Can someone confirm that the top of the separator can be popped off in order to drill it?

special tool

Why do you want to drill t?

pikey7

Exactamundo. If things are fine, then leave it.

Mike Murcia

I'm deleting the venturi and posts in the archives have suggested drilling it to increase vac in the crankcase. I don't really need extra vac to pull in vapors to a catch can. I just want to ensure I don't lose too much vac in the crankcase.

pikey7

you wont. Later cars didn't have the venturi, and didn't have a larger hole either. Even if you fit a catch can, the improvements are debatable.

Mike Murcia

The later cars did not have a larger hole? Good to know. Thanks guys.

eclou

The point of increasing the hole is when you run more boost in a car than stock. Someone had a formula suggesting that the amount of crank pressure increases dramatically when boosting beyond 1 bar.

MichelleJD

Drilled mine earlier today. I had the AOS off the car. I drilled it upside down then blew a ton of compressed air through it. However, I have a catch can.

Crazy Eddie

Mike
That top on the ASO is removable ...
It requires a bit of finesse and patience
I would also do it when the ASO is warmed up so the plastic wont crack
there are tabs at the top that have to be punched out of the way with small (tiny screwdrivers)
I was told that if the top is popped off that the O ring should be replaced
That is not a part that is available from Porsche as they sell the whole unit only ...
What a surprise
I have a contact who sells them, in fact I am going to get one ordered this week.
Let me know if you need one
regards
Ed

special tool

You guys need to pay particular attention to what you are doing with this crank vent system. Dead-end cannisters are NOT a good idea. The turbochargers like to have vacuum!!!!!! If there is not sufficient vacuum, oil will back up the drain and slip past the turbo seals and smoke. This is VERY difficult to diagnose - the local knucklehead mechanic will tell you to do the head.
Remember what I told you.

kasturbo

Any numbers to back this claim up? So your saying the Lindsey catch can is a bad setup and idea? Funny that my smoking turbo stopped after I put a catch can on and drilled out the aos. How do you know that your smoking turbo problems aren't caused by too much oil pressure or too much back pressure on the hotside?

I'm not saying your wrong, or that I know anything, but you made a bold statement with out any numbers to back it up. I'm tired of the "sky is falling" type comments that come up all too often on this board.

special tool

You can trust that bull**** doesn't come from me. I do EVERYTHING myself. I know what I am talking about.

Kevin - make sure that your filter stays clean.

Also - of course I am right - I am siding with Porsche! I am saying that there is a reason it was designed like this. People/venders say - well if you need vacuum, your rings are bad. WRONG!!!!! It is because of the design of the trubo drain!!
The best thing to do is to put an inline catch can (very freebreathing) and continue to route to intake vacuum. In this way, you will not be TESTING your turbo exhaust-side seals.

Obviously, I have EXPERIENCED the faults of improper venting.

stewardx

Also - of course I am right - I am siding with Porsche! I am saying that there is a reason it was designed like this. People/venders say - well if you need vacuum, your rings are bad. WRONG!!!!! It is because of the design of the trubo drain!!
The best thing to do is to put an inline catch can (very freebreathing) and continue to route to intake vacuum. In this way, you will not be TESTING your turbo exhaust-side seals.

Perhaps Porsche vents back to the turbo so the customer doesn't ever have to
drain some tank on their car older the engine. It is self sustaining. Even on a
car with shot rings. The way average car owner would expect.

If you put a free breathing tank between the AOS and the Turbo, the vacuum your
talking about it lost at that middle tank. It's no longer doing anything
vacuum wise to collect oil from your block.

Wes

Campeck

I have a catch can that is still vented to the intake. It cleans out the oil and leaves it in the can while it still has vacuum from the intake. no more oil coating the inside of my engine!

special tool

Wes - I am talking about a CLOSED tank, not an open, filtered tank. Obviously, this retains the vacuum.