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In the middle of putting a MSD Air Force intake on my car and got my Ls6 intake off when I noticed oil in the intake ports on the passenger side head and what looks to be excessive. The driver's side ports are pretty clean. This is after 1,000 miles on a H/C build. The first picture is passenger port, second picture is driver's port.
PCV setup - passenger valve cover to catch can, catch can to check valve, check valve to intake. I should mention in the beginning I did run it the same way but without the check valve and my catch can was filling up fast with not many miles put on it so I put the check valve in and it is much much better.
Now I'm sure it sucked in plenty of oil before I put the check valve in but what I don't get is why the oil pulled so hard to the passenger ports..... ?
Looking for advice or maybe a underlining issue that jumps out to someone about why the oil pulled so hard to that side..... Minor intake manifold seating issue causing a slight vacuum leak in the driver's side ?
Any input would be much appreciated. Thanks much guys. Pictures below.
Another thought, could it be just because the pcv return inlet is on the passenger side of the intake manifold that it all pulled to that side before I was running a check valve and sucking in oil.......
97 kpa at idle means a vacuum leak or unmetered air getting in somewhere. If your catch can is filling up that much youd prob be better off fixing your excessive blowby issue. The pass valve cover doesnt normally go to the pass side of manifold either though. it will either go to the elbow on tb or a tube after the maf on the intake tract.
You running an ls6 valley or driver valve cover tied into pcv also?
Instead of spending 1k on an intake, spending 1k on the bottom end would have been a better idea honestly.
I'm not running Ls6 valley pcv. Driver valve cover to catch can, catch can to check valve, check valve to intake manifold, passenger side valve cover to elbow on throttle body.
If you are having that much of a pcv issue its likely due to rings or piston to bore clearance. I meant get the bores checked out and machined and a fresh set of rings etc to help combat that.
Do you have the dual port pass valve cover? meaning a port on front and back. The way the system should work like that is, place an inline pcv valve in the tube between driver valve cover and catch can. That back part is just an open orifice and you need to restrict the air going out. After that it can go right from catch can to sid of intake. The front pass valve cover is just an open tube only and relies on the bafflin in the valve cover to cut down on the oil mist. If necessary you can "neck down" the tube or put a small restriction in it also like another pcv valve etc to help keep the amount of airflow down. it will help. That is why the factory Y'd pcv hose system has a pcv valve in it right before the intake. To help meter the air.
Ya, I hear ya. Tho oil consumption is no longer a issue. I'm assuming all the oil on the passenger pic above was from when I was sucking in oil which I am no longer doing.
Oil consumption is at pretty much zero now.
I was wondering if there was a reason cylinders 1,3,5 &7 all look clean like the driver's side pic above and cylinders 2,4,6 & 8 all have oil like in the passenger pic above.
Did you put sealant on your rocker bolts going into the heads? With ported heads you have to put sealant on the rocker bolts since the rocker bosses inside the port are ground down exposing the bolt hole.
Did you put sealant on your rocker bolts going into the heads? With ported heads you have to put sealant on the rocker bolts since the rocker bosses inside the port are ground down exposing the bolt hole.
I highly recommend upgrading to the LS6 PCV system. The original LS1 system isn't that great even when working.
Didn't see this till now, thanks much for the input. I will do that this spring. The stock style is definitely a pain to get working right with my setup
If oil is coming in through the pcv, the back of the throttle plate will be coated with oil. Also, re catch can, make sure it contains some type of filter material, if it's empty it's worthless.
07-11-2017, 04:08 PM
PCV/Passenger head, oil in intake port 
