PVC and Turbo help
Thread Starter
Joined: Jun 2003
Posts: 651
Likes: 6
From: NEW YORK INTERNATIONAL RACEWAY PARK
PVC and Turbo help I've read a lot and the more I read the more confused I'm getting with all the different opinions. I have a stock ls1 with h/c LS6 intake stock valley cover and huron speed turbo kit. I just turned the boost up to 7bls after being 4-5 for the last couple years. I drive few thousand a summer.
I currently have the stock check valve in DS valve cover, routed to the PS valve cover just like stock, an oil/air separator was added then a PCV valve and into the intake. I also added a large breather to oil fill cap. As I increase boost is this sufficient?
I was considering twin 10 an lines from the valve covers to a catch can and blocking off the intake ports. Is this okay as I'm not pulling any vacuum from the crank case?
At some point the motor will get rebuilt(347) and the boost will go up to 15lbs.
I have spare valve covers, can weld aluminum etc IDC but buying a $400 catch can set up isn't an option.
thank you for any help
I currently have the stock check valve in DS valve cover, routed to the PS valve cover just like stock, an oil/air separator was added then a PCV valve and into the intake. I also added a large breather to oil fill cap. As I increase boost is this sufficient?
I was considering twin 10 an lines from the valve covers to a catch can and blocking off the intake ports. Is this okay as I'm not pulling any vacuum from the crank case?
At some point the motor will get rebuilt(347) and the boost will go up to 15lbs.
I have spare valve covers, can weld aluminum etc IDC but buying a $400 catch can set up isn't an option.
thank you for any help
Last edited by Mustang Hat'r 2; Jul 14, 2024 at 04:53 AM.
TECH Fanatic
Joined: Jul 2022
Posts: 1,032
Likes: 389
From: Alaska
You can fabricate a catch can for a bit less than $400
As well, no reason to run threaded AN fitting on BREATHER hose, which essentially operate at ambient atmospheric pressure:
1/2 or 5/8 Heater hose will work..
As well, no reason to run threaded AN fitting on BREATHER hose, which essentially operate at ambient atmospheric pressure:
1/2 or 5/8 Heater hose will work..
So, I ran the stock PCV system w/ 3/8" lines and Mighty Mouse PCV catch can on my last turbo LS1.
It was good up to about 10 lbs. of boost, above that the small 3/8" lines couldn't keep up and I blew my oil dipstick out.
I kept the MM PCV can, removed one of the 3/8" fittings on the can, welded on a -12AN bung, ran a -12AN line from the driver's valve cover to the can, kept the rest and added a remote filter with some 3/8" line from the valve cover to the inner fender on the passenger side to help protect against oil being pushed out which never happened so I assumed it worked.
This worked well up to 14 lbs. which is as high as I went but MM confirmed it would handle more boost while maintaining PCV function.
My current car uses dual -10AN lines to an atmosphere vented catch can which also works very well.
You could also do an exhaust evac style system which others on here have said works very well so you have several options.
It was good up to about 10 lbs. of boost, above that the small 3/8" lines couldn't keep up and I blew my oil dipstick out.
I kept the MM PCV can, removed one of the 3/8" fittings on the can, welded on a -12AN bung, ran a -12AN line from the driver's valve cover to the can, kept the rest and added a remote filter with some 3/8" line from the valve cover to the inner fender on the passenger side to help protect against oil being pushed out which never happened so I assumed it worked.
This worked well up to 14 lbs. which is as high as I went but MM confirmed it would handle more boost while maintaining PCV function.
My current car uses dual -10AN lines to an atmosphere vented catch can which also works very well.
You could also do an exhaust evac style system which others on here have said works very well so you have several options.
On The Tree
Joined: Feb 2022
Posts: 196
Likes: 72
From: Grand Rapids, MI
My simple setup is... truck drivers side valve cover with rubber grommet in the back. Bought a 1/2NPT to 3/4 barb fitting, it threads right into the rubber grommet. Run single 3/4 rubber hose to catch can, then single 3/4 hose to just behind the air filter but IN FRONT of your turbo. This way you get slight vacuum everywhere and no oil back into the intake, and your girlfriend/wife can ride in the car and not get slaughtered with fumes.
I have forged LQ9 7875 turbo with 15psi boost and no oil leaks, I tried an open/vented to atmosphere catch can but said fumes made the girl get headaches and my oil got dirty really quick.
I have forged LQ9 7875 turbo with 15psi boost and no oil leaks, I tried an open/vented to atmosphere catch can but said fumes made the girl get headaches and my oil got dirty really quick.
Launching!
Joined: Jan 2002
Posts: 299
Likes: 41
From: Detroit, Murder City
