Ever since I installed this motor, I had a great deal of intake oiling. Never figured out what was causing it. All sorts of solutions on the internet. I had it with the Kenne Bell, I had it with the RPM II, and I had it with the Holley Systemax. This is what it looked like at the throttle body and it not only ran down the air tube past the MAF into the air filter, but also back into the plenum.
So I got with some others (Pete and a local friend here) and organized a plan of attack. We decided to relocate the PCV valve to the drivers side valve cover and delete the primary unit behind the manifold.
We had proven the PCV behind the manifold was the source of the excessive oiling using an oil separator. This was after just 30 miles of driving.
This is what we came up with.
The new PCV on the driver side valve cover.
This is where it is plugged into the plenum, in the same spot the stock PCV would have been plugged into.
Elimination of the stock PCV location involved keeping the wire mesh in place to prevent foreign object intrusion into the motor, and installing a plug into the existing stock PCV grommet. An excellent seal is required. You do NOT want to introduce oil or vacuum leaks into your motor with a poor seal.
I used a 1/2 inch plug that came with one of my intakes, but you can also get any brass 1/2 inch plug from your local hardware store. It is a very tight fit, so I suggest getting one you can screw back out with a tool in case you tear the lip off the rubber grommet trying to remove it later on.
I installed a non-breathable cap in the rear of the passenger side valve cover that would accommodate a tube to the throttle body, similar to the stock version running from the oil filler cap to the throttle body. It is important to use a closed cap, and not one vented to the atmosphere. Everything after the Mass Air is metered by the Mass Air, and is air that is already accounted for. By using a vented cap, you allow unmetered air into your crankcase and basically introduce a vacuum leak.
It is necessary to resupply the crankcase with fresh metered air to replace the air that is drawn out by the intake vacuum working hand in hand with the PCV system. Without this opening, you will end up with a great deal of vacuum in your crankcase created by the vacuum pump that is your manifold in conjunction with the PCV, and have no new air going in. It's like sucking thru a straw, and then plugging the other end with your finger. If you don't let new air in to replace the gaseous or dirty air being drawn out of the motor, you will defeat the purpose of having a PCV system and end up with basically a dead air vauum reservoir in your motor.
There is question as to whether there will be oil shot up into the intake during hard acceleration on the passenger side cover, since the cap and line leading to the throttle body is located in the rear. This would happen to due inertia and all the oil going to the back of the valve cover, but so far it hasn't happened. If it does, I will simply drill a hole in the front of the valve cover, relocate those units up forward, and install a non-vented breather cap in the rear behind the throttle body to plug that hole.
As of now, there is no oiling at all in the intake after relocating the PCV from the rear manifold to the drivers side valve cover. I used an oil separator briefly, and now realize I no longer need to use one.
So there you have it.
