I built this new engine and it's the first one I've ever built. I've also seen the effects of what a closed pcv system does to the injectors, intake manifold, throttle body and valves on the LS1 that was removed after the No. 6 rod decided to go. Yes this was an emissions legal engine than ran for over 150,000 miles and served me well.

Like I said i have the ability to run either system and right now I'm on the fence when it comes to closed pcv systems on my street/strip car. It's not my daily driver keep in mind but I can you tell you first hand that my breather can set up had no ill affects to my cylinder rings sealing or my oil getting all gunked up after 3,000 miles! Engine gunk is a result of people who don't make the necessary oil changes.

 

What an excellent opportunity to learn from experience. How do you think oil gets onto the throttle body, and into the intake manifold, prior to the vacuum source for pcv? (Which if often near the rear of the intake). Which direction of PCV flow does it look like caused the coating to appear? And what does air filter quality/restriction have to do with that oil film?

As maintenance goes, Removing the intake manifold once every 50-100k (1-2 times in that engine's life) to clean it out is not terribly difficult or unexpected, some new DI engines require this sort of removal and valve cleaning due to carbon buildup that gasoline no longer washes away. Does removing the pcv on those engines keep the valves clear? The oil also probably helps prevent oxidation to some components as well (I don't mind knowing my throttle body has some oil on it) and is a comforting thing for me to find inside the air path of an engine, if it is clean oil residue. This is a very powerful diagnostic insight we just brought up: The amount, and quality of the oil residue found inside a high mileage engine is an indicator of engine health. If it has particulate embedded in it, rough looking residue, pitting of the metal materials in the air path, it means the air filter quality was poor for some significant duration of engine operation. The oil helps us trap and "see" what the air filter is letting through after 30k or 50k miles (these are long-term engine diagnosis skills). I like to see a very light coat of oil, clean looking and clean smelling, just like you would expect in a well maintained engine. Even if it had been recently cleaned you would still see embedded materials and metal pitting whenever air filter quality is diminished for some duration, especially in the throttle body region, I guess the tiny objects are likely to smack the blade at high speed or something.

The air filter restriction (or pressure between the engine and filter as measured with a gauge) is a critical component of oil flow in pcv systems. More restrictive filters mean lower pressure where the crankcase gets its fresh air from, and during wide open throttle this means more oil residue will flow towards the engine throttle body. A perfectly healthy engine with a very clogged air filter is more likely to send oil all over the intake manifold/throttle body as if it has a blow by problem, because low pressure between the filter and engine is drawing oil from the crankcase readily. This just means the filter is/was super restrictive- i.e. it might be a very high quality filter which is simply clogged up at the moment in time, and hasn't been replaced, it is not a sign of a bad engine or bad PCV system!

 

I typically put a breather on both valve covers and that's it. Can't say I've ever had an oil smell under the hood. You know what keeps a motor cleaner than a PCV system? Changing the oil. There's no need to go overboard on PCV unless the setup is making a ton of hp. I will share 1 trick on my old turbo car though. People mentioned on page 1 about putting a bung in the exhaust and letting it pull a vacuum, but then mentioned that backpressure could prevent that from working correctly. On my setup we put the bung into the wastegate dump tube, no backpressure to worry about and pulled a vacuum under boost when the wastegate opened and you need the vacuum the most. Never had an issue with blowing dipsticks, motor was squeaky clean, and like 3 owners later it's still putting a smile on people's faces.

 

Thanks to everyone who had a positive, constructive reply...... And I agree, the best way to keep an engine clean is to CHANGE THE OIL. I prefer to drain it when it's hot, so most of the contaminants in suspension in the oil will drain out with it. I'll post pics once my catch can, AN hose and hose ends arrive in the mail.

 

Heres the catch can setup! Came in the mail yesterday. A lot like the idea 3 window had!

 

It’ll work fine.

 

Thanks again for the idea friend!!

 

This is an amazing idea! But, if you used two right side (passenger) valve covers to make your PCV catch can setup, (which is genius by the way), where do you add oil? Do you unhook the AN fittings and twist the pcv adapter off each time? Is there a trick adapter that allows oil addition to that billet -10 fitting? oooh that would be another good idea!

Here's the Earls fitting to adapt to oil fill / AN.

I really would like to do the Holley 241-113 taller valve covers that delete the coil brackets, but I also want to run a valve cover PCV to catchcan set up jut like you've got, but am trying to figure out the most cost effective option. I could buy two sets of the Holley covers, but that would be north of 500 bucks, and then I'm guessing I'd be where you're at, wondering where I add oil?

I could buy the Motion Raceworks covers, but then I'd still have the ugly coil brackets. I could buy the cheaper BTR valve covers, but then again, I'd still have to use the ugly coil brackets.

Someone needs to make valve covers that utilize the offset 72mm coil bolt spacing that also has integrated AN fittings for PCV systems.

(sorry for the thread hijack!)

 

Yeah, you simply unscrew one of the AN hose ends from the adapter (usually the passenger side), then unscrew the adapter from the valve cover. Pour in oil as required. Couldn't be more simple.