Catch can use question...

[Onefast99gsx]

Well my turbo has been sent off to PTE for repair. I've been emailing back and forth a few times today. He didn't say anything about the size of the oil feed line. He wanted to know when i thought it was leaking oil. All i could tell him was that i noticed the burning smell the most just after a wide open pull. That would be when oil pressure is at its most, right? Well, then he thought maybe i have a crankcase venting issue. I emailed him back pretty much the same as below. He hasn't gotten back to me yet.

On the 4g63 valve cover are 2 fittings:

-One is the line that goes into the stock intake pipe to the turbo inlet
-The other is the PCV that feeds into the stock intake

I have both of those hoses going into a JAZ catch can. It's a 1 pint mini breather can with 2 nipples. See below link for a picture of it.

http://www.jazproducts.com/index2.htm

Question: Is this setup of mine bad by going into that catch can? Am i causing a problem by running it and therefore not getting crankcase pressure out? Please enlighten me on whether what i'm doing is really bad.

Thank you.

[Shane@DBPerformance]

Did you remove the PCV from the other port and stick a normal hose barb on it instead? Otherwise it wouldn't work so good without vacuum to open it.

[Onefast99gsx]

Hi Shane, thanks for your reply. No i just left the stock untouched PCV valve where it was at and just ran a hose from it to the JAZ can.

Hmmm. Interesting. I should have either gutted it or used a regular barb? Perhaps it's a thought. Can excessive crankcase pressure cause knock?

[Goat Blower]

I seem to remember doing some research a few years ago and seeing a link to excessive crankcase pressure and small amounts of knock.


I have both fittings running through vacuum tubing to atmosphere, no PCV valve. The thing I've noticed already is there is alot of pressure at WOT, enough to break my vacuum tubing twice. I'm going to run -8 or -10AN lines out of it to a custom aluminum one-quart catch can when I get around to it. I believe Brent has something like dual -12AN lines out of his.

[Onefast99gsx]

Hey, thanks for the reply. Maybe we're onto something here. What are you using to see this pressure in the crankcase?

[CDeutsch]

If you decide to get rid of the PCV (actually you really should like Shane said), I would just skip the gutting and use a hose barb. I fought with gutting mine and never did get the plunger out, but your results may vary.

[Goat Blower]

Hey, thanks for the reply. Maybe we're onto something here. What are you using to see this pressure in the crankcase?
Just the fact that it blew a vacuum hose apart twice. I had both tee'd into one line with a filter on the end of it, now I have both hoses separate to atmosphere, no problems since.

[Onefast99gsx]

Thanks for your input guys. I will do so when i'm ready to get the car going again.