Was removing my intake last night (getting rod mod done) and noticed that I still have oil inside the intake. I do have a good oil separator installed in between the valley cover and the intake manifold (what I've seen referred to as the dirty side). My question is what is the other hole used for? It's to the right of the pcv entrance. While I do have quite a bit of experience using oil separators on engines, my GS has a dry sump LS3 and not exactly sure how this plays into the equation. I do know there are several lines coming off of the sump tank and oil might be coming from there? Looking inside the hose running from the separator into the manifold, I can't see much of any oil at all and I do know that I have to empty a small amount of oil out of the separator from time to time so I know it's working. Any ideas where the oil could be coming from? It doesn't seem to be from the line before the throttle body because the TB is very clean on both front and back. I have heard of people running dual catch cans and not sure if I need one. I've also read something about dry sump owners running about half quart low on oil to prevent oil from being sucked up into one of these lines? Any advice or suggestions would be great, thanks everyone!

 

Any ideas?

 

Your oil separator/catch can won't collect 100% of the oil vapor. Some will get into the intake no matter what.

I wouldn't worry about it if you are catching the majority of the oil vapor in the catch can.

 

Beef97 i am a little confuse here, by oil separator do you mean a catch can. Sorry for my ignorance. Thank

 

What else is done to the car?

 

And what catch can is it?

 

It's a Bob's Machine catch can. Just the typical bolt on mods, headers, etc. No forced induction or nitrous.