i recently took off my plenum (with the 1/2" spacer) and i noticed a LOT more oil in there that there was b4. has anyone re-opened up there plenum after installing there spacer? is there suppose to be a gasket on top the spacer AND below?? thanks

 

Yes, two gaskets. You reuse the OEM gasket that was originally in place and add the MD gasket that was shipped with the spacer. I have the 5/16" spacer but I can't imagine that the gasket set up would be different.

 

There is no difference in oil from before to after.

 

Ditto on Easein2itG's comments.

With regard to whether the 1/2" spacer is responsible for depositing more oil into your lower collector . . . Based on what I have learned from GEE_PASTA and DaveO, I would say that the spacer is not the direct cause of any additional oil, which you may see. Since you installed the spacer, you may be driving your car a bit harder, at times. Based on my own personal experiences . . . What little oil you are seeing is only a small percentage of the oil that has been introduced into your plenum and digested by your engine.

If so desired, read up at the following 2 links and decide for yourself.

https://g35driver.com/forums/engine-drivetrain-forced-induction/97246-catchin-oil.html

https://g35driver.com/forums/engine-drivetrain-forced-induction/97390-makeshift-oil-catch-can.html

 

I opened up my plenum twice (MREV2 added to ½” spacer), each time after 9K mi, and there was approximately same amount of the oil there both times. This time I installed oil catch can and after couple of hundred miles it is almost half full!?

 

if any of you taken off the lower plenum you'll see that the outlet of the PCV system is hooked up to the front of the plenum. then it goes into a valley. In the valley you'll see little passages to each runner.. where the oil can get sucked into the cylinder and be burned =).. so alot of oil in the plenum is normal just the design of the PCV system.. a even better way to do it is to hook the outlet up to the exhaust so it just blows out

 

I have spoken with 2 of the top local Z and G tuning shops and with 1 Infiniti mechanic with regard to this. After having spoken with these people . . . All I have to say is that . . . Yes, this PCV/lower collector set-up was per design. However, that does not neccessarily mean that it is a good design.