Ls7 Compression test

[NotSure]

I have to add, the original check valve that came with the kit seemed to take a little bit of pressure to unseat it when blowing through. This was after being installed for about 4 years. They have changed the design at some point. The natural colored one in the pic is the old style and consisted of a spring and rubber seal. The newer one (blue) is just a plastic ball that is free to move about and takes nothing to unseat when blowing through one way, and fully seals the other way. How much contribution the old check valve had to keeping pressure in the crankcase, I don't know.

Elite Engineering check valve - old and new.jpg

[kingtal0n]

Look I'm not on here to argue or fight over this or anything else.

I don't fight with you. I respect you and are one of the only people on this forum that is objective.

What you don't seem to realize is how much oil makes it's way into via an OE system. I have literally removed intake manifolds with 100k off of 5.3l's and poured a full quart of oil out of them.

And I am saying it is in fact not due to the OEM Pcv system and instead has to do with people not measuring their crankcase pressure and performing mods like cold air intakes.

there would not be a quart of oil or anywhere near that amount of oil in any OE intake manifold if the engine has the correct crankcase pressure drop at wide open throttle. Period. The catch cans and the oil in the intake manifold are merely BAND_aids for people not understanding how PCV works and how they brand new air intake filter causes oil to blow into the intake manifold.


I'm at 60k with a 18psi of boost on OEM Intake manifold and OEM pcv system and I haven't got any weird amounts of oil in my intake manifold. Nor any other of hundreds of engines i've setup properly over the last decade or so once I figured it out. So, Do math

[Alvin]

It is not unusual to pour out serous amounts of oil from a LS intake. Completely stock. Trucks, cars, new, old.

[kingtal0n]

The only bad way of installing a catchcan is putting in the type that has a breather. If it's sealed then it does only good. Stock size lines and about 8 inches extra length to get it routed. I mounted it to the passenger side head, so it's right there near stock provisions.

Catchcan is one of those mods that's like a cold air intake. Often done wrong because the majority of people are ignorant. How well do you think those types take care of their vehicle? Correlation vs causa...

Pressure loss in a pipe for you


I already gave the math behind friction induced pressure loss for a pipe of the PCV system. You ignored it I guess

You can't just add lines to an existing provisional fluid pumping system without making new calculations and measurements.

The can is sealed so what. The longer the line becomes between the crankcase and region behind the air filter, the more the crankcase pressure will rise, the more oil will blow out of the engine. It needs to be measured. Adjusted properly.

Reiterate:
As the hose between valve cover and air intake pathway becomes longer (Friction) the crankcase pressure will rise higher causing more oil to blow out of the engine.
The mere act of adding a catch can or removing the air filter (free filter flow) will cause oil to blow into the intake manifold or out of the engine other places. Period.

You must measure the pressure. How can you be so adamant to understand that measuring fuel pressure is essential but measuring crankcase pressure isn't needed. Do you measure tire pressure? No? That sucks. DO you measure boost pressure? No? that sucks. Coolant pressure? OIl Pressure? You just have to measure it. If you measured it and fix the pressure you can run all the catch cans you want. But there wont be any oil in them lol. When a piston ring breaks and oil is blowing out of the engine, then yes you will need a catch can, that is what they are for, broken piston rings that leak compression which blow out oil from the engine. When I see a catch can I know right away the engine is trashed. Broken.

[kingtal0n]

It is not unusual to pour out serous amounts of oil from a LS intake. Completely stock. Trucks, cars, new, old.

I know people say that but I have not had this experience with mine. You can't know for sure what happened to those engines that causes that but it isn't in the design that is for sure 100% or I would have noticed.

For example people do 5,000+ mile oil changes. You do that for 100k+ and guess what happens to the oil control rings? Now you have oil blowing out of the engine and excessive leakdown and cylinder bore wear. That wasn't a design issue it is a maintenance issue. Another example failure to replace or test PCV valve, the OEM pcv valves on my engine LEAKED even the brand new one from the box leaked I had to install a toyota supra PCV valve to prevent the leaking. Nobody is pressure testing their shit they don't even realize the OEM pcv valve is leaking. Again, not a design issue, just a maintenance and education issue. You have no way to show data or prove to me that anything other than maintenance and education has anything to do with oil in the intake manifold based on my observations with a worn out ass 5.3L with over 240,000 miles that doesn't blow any oil anywhere at 18psi 600rwhp for 60,000 miles. There is nothing wrong with the engine even with tired out old worn compression it seals up tight to my pressure tests and adjusted crankcase pressure 1.2"Hg at wide open throttle no oil leaks no oil smoking no drips no seepage no problems. gg

[NotSure]

It is not unusual to pour out serous amounts of oil from a LS intake. Completely stock. Trucks, cars, new, old.

+1000. Bone stock soccer-mom grocery-getter before I got ahold of it and literally destroyed the pcv system. Oil dripping all over the freaking place from that manifold when it came off. But, maybe Mrs. Mom secretly swapped out that K&N for an AC Delco just before I bought it, you just never know!

[kingtal0n]

+1000. Bone stock soccer-mom grocery-getter before I got ahold of it and literally destroyed the pcv system. Oil dripping all over the freaking place from that manifold when it came off. But, maybe Mrs. Mom secretly swapped out that K&N for an AC Delco just before I bought it, you just never know!

Or failed to maintain the pcv system. Maybe a line broke or got cracked and leaking. Maybe the pcv valve gunked shut or open position. People dont test or inspect these things and this leads to problems of course. But it wouldn't happen if they had paid attention and actually inspect the engine and carefully replaced the pcv hoses and pressure tested it and measured the crankcase pressure. Nobody does it so everybody blames the engine. But the engineers who design it know exactly how the engine is going to work and perform and they give it to you perfectly in good shape, then downhill from there because 99% of motha fuckas dont even know what PCV does or that it has anything to do with oil leaks. Or even change the damn oil often enough.

[NotSure]

No pcv valve in this engine as-delivered from the General. But anyways, I thought you said that oil passing through the pcv system was good, to give everything a nice rust-resistant coating?

[kingtal0n]

My compressor wheel at 30k


My oil streak inside the intake tube behind the air filter


It was so dry so little oil I manually oiled my compressor wheel with a bit of WD40 followed by a spritz of SAE30 weight and a gentle wipe.
Notice the slight oil trail captures some fine particulate. As it does in turbo JDM engines, prolonging turbo lifespan. I changed to an off-road filter now to up the ante.

Before I used the engine I did thorough inspection of bottom end without taking it apart




I built an entire car around PCV to show its not the engine that has a problem. Its your thinking that has a problem, the copy and paste, the 'I see oil so I assume _______ ' without knowledge of engineering principles.


I am the only one you people know who is measuring and testing these things on pretty much any engine let alone a 5.3L with over 200k miles. You can take the data point and engineering evidence or you can keep making the same mistakes for 20 more years.

[GHuggins]

I've had their E2-X catch can setup installed since my blower install. The only thing the dual inlet can does is add a second port to the can that you connect to the intake tract pre-throttle body. Unless you are referring to a different one, there is nothing special about this dual inlet can other than an added fitting on the "clean side". This kit also includes a replacement oil fill cap that has stainless mesh in it, with a hose fitting to also connect to the intake tract for a secondary avenue for crankcase gases to get pulled out, and to provide fresh air into the crankcase when not under boost. 2 check valves are included to install in the appropriate places for boosted applications. For what it is worth, I measured up to 6 kpa crankcase pressure at 8 lbs boost with this setup. Since then I have pulled the pcv connector out of the left rear valve cover and drilled it out (from 1/8 to 3/8"), installed the expensive ME Wagner adjustable pcv valve, put a larger fitting in the intake tract, and max crankcase pressure is now around 1-2 kpa. Still could be better. Measured with a GM MAP sensor, signal fed into a MVPI1 Pro analog input. After drilling out the valve cover connector, I tried a stock pcv valve (unknown application) between the catch can and manifold vac port, but it was not pulling vac on the crankcase in part throttle conditions. Good luck finding any flow data to pick an appropriate pcv valve. This is why I went with the ME Wagner, it gives you an adjustment for idle and part throttle, then acts as a check valve under boost (they only tested to 20 psi for you big HP guys).

I had the need to pull the blower back off shortly after installing it for injectors (few hundred miles?), and there was still some oil puddling in the lower intake. Never took any measurements, but usually only got a couple tablespoons after a few hundred miles. In the wintertime on E85, the catch can would trap a bunch of condensate/oil sludge, very nasty.

Are you running their venturi? I have one customer that just installed this kit. I know they literally just changed it and gave him the newer updated venturi valve that just came out of testing. I was curious if it actually pulled vacuum under wot. His is a Procharger setup and I get the feeling that it's more designed for turbo's and centri's in mind especially with how a venturi works. I'm actually very surprised it's not showing a vacuum leak at idle with the one tube feeding unmetered air to the crankcase. The whole reason he started down this road in the first place. Fueling was all over the place with Procharger's open valve cover element. It seems to be working so far from him checking it.

[NotSure]

Ok, now I see the venturi valve on their website. I don't have that, both hoses (one from the catch can off the left valve cover, and one off of the right valve cover) terminate in the intake duct pre-TB close to flush inside, so the intake air just passes over the top, which does draw slightly as tested on the bench when forcing air through the tube. I may try to do a venturi sometime and measure if any improvement. For an experiment, I did try to put the right bank intake duct attachment in at 90 degree facing into the intake stream (to push air), with the left bank connection flush on the inside, in an attempt to keep the pcv flow going the same direction through the engine when transitioning from vacuum to boost, but it did not work. Then I made both fittings in the intake tract flush, which lowered the WOT crankcase a couple of kpa, so it seems the engine wants to vent out both sides under boost. Wish I had taken pictures. This is with a Whipple, so yeah the venturi wouldn't work as well as with a turbo/centri. I am kind of guessing that it won't make a noticeable difference in my application.

[NotSure]

Rob, if you have a stock LS7 valley plate, it has a baffle system attached to the bottom, and the hose barb should have a 2.5mm fixed orifice inside.

I'm not clear on how you have things routed now, I think you deleted the oil tank and put the catch can in its place? Do you have a way to measure crankcase pressure under all loads? Single digit kpa.

[GHuggins]

I don't fight with you. I respect you and are one of the only people on this forum that is objective.



And I am saying it is in fact not due to the OEM Pcv system and instead has to do with people not measuring their crankcase pressure and performing mods like cold air intakes.

there would not be a quart of oil or anywhere near that amount of oil in any OE intake manifold if the engine has the correct crankcase pressure drop at wide open throttle. Period. The catch cans and the oil in the intake manifold are merely BAND_aids for people not understanding how PCV works and how they brand new air intake filter causes oil to blow into the intake manifold.


I'm at 60k with a 18psi of boost on OEM Intake manifold and OEM pcv system and I haven't got any weird amounts of oil in my intake manifold. Nor any other of hundreds of engines i've setup properly over the last decade or so once I figured it out. So, Do math

Ok, I think where the problem here is, is that you're focused on gen 3's or older. GM changed things in the gen 4's and in my honest opinion they didn't test them enough. They made these changes mainly for fuel economy and power. In doing so they introduced 4 primary design flaws that they later tried to address through the years.

These issues were low tension piston rings - low drag = more power, less friction, better fuel economy and more power / Next was DOD - in order for DOD to function oil pressure is maxed out to unlatch the internal pins / PCV was removed - went to fixed orifice / oil pressure relief added into the oil pan to divert that high DOD oil pressure back into the pan.

What wound up happening is during DOD oil was sent to that oil pressure relief valve and was then sprayed out right onto the crankshaft. Crankshaft then whipped the oil around into the base of the cylinders. As the engine was heat cycled the oil then baked, crystallized and turned into carbon causing the oil control and second compression ring to seize in the ring lands. Yes the engine's still ran fine, but all oil control was gone. PCV being fixed orifice would allow any oil getting into the valve cover to enter the intake system. This is probably the biggest design flaw. With the rings being seized this made this issue worse. On top of this lifters were over oiling. You would have one or two spray an oil stream 2 or more feet out of the pushrods. Again making the fixed orifice valve cover issue worse.

GM's solution at that time. Re-ring the engines, install updated glued together valve cover, install an umbrella over the pressure relief in the pan, dump all of the oil out of the intake manifolds - intake manifolds on LS's are multi chambered. You have the primary you see when opening the throttle plate and a secondary rear chamber. The secondary rear is where all of the oil builds up and due to the oil thickness/viscosity it is hard to get the engine to suck this through - again - design flaw. It requires cleaners to thin it out and then you can suck it through. They also replaced the lifters if issues were found and valve seals if apparently leaking. Basically a full overhaul often by 60000 miles.

Now with that being said GM as since gone back to pcv's and using catch cans to aid in keeping oil out of the induction systems. These are more so also because they went DI and with DI there is no way to clean the intake valves via fuel spray.

Just because it was designed by engineers, doesn't mean it's right and has no problems. Yours being turbocharged will actually help yours a little by sealing the rings, which are already higher tension and might actually help at cruise and light throttle to scavenge better.

Gen4's just have a lot of design flaws circling around the fixed orifice system. Best easily available solution is a catch can system. Either that or redesign everything. I do agree vacuum is 100% necessary along with a good system. I just also think this needs to include something to keep oil out of the intake. Minus the small vapor that is Also not sure on the wd40 anymore. Not sure i would use it in the engine since they changed it. Seems to mess with rubber more now since they got rid of the "flame" possibility and made it to where it wouldn't burn...

[gtstorey]

"just because it was designed by engineers"

add "but cut by the bean counters/accountants"

[SiriusC1024]

Changed diff oil today. Figured I'd drain the catchcan, too. Here's ~600 miles. 189000 on the clock.

can1.png

can2.png

Oil mixed with water and smelling of partially burned fuel. You know, condensed crankcase vapors. Preventing this from entering the cylinders is harming my engine how?

[LS ROB]

Rob, if you have a stock LS7 valley plate, it has a baffle system attached to the bottom, and the hose barb should have a 2.5mm fixed orifice inside.

I'm not clear on how you have things routed now, I think you deleted the oil tank and put the catch can in its place? Do you have a way to measure crankcase pressure under all loads? Single digit kpa.

I do have the hose barb on the valley plate. I converted the ls7 to wetsump to do away with the oil tank. My routing is as follows now: Clean side- I have a 3/8 line from the intake tube (after MAF and before TB) going to both valve covers. The valley plate barb line is 1/2" and goes into the catch can, then from the catch can to the intake port behind the TB. I do not have a way to measure the crankcase pressure at this time. I seen the Wegner unit is guaged by how much vacuum you have. I may end up going that route, but if i can rig up a MAP sensor, i may do that. I'll have to look into that more.

[LS ROB]

Changed diff oil today. Figured I'd drain the catchcan, too. Here's ~600 miles. 189000 on the clock.

can1.png

can2.png

Oil mixed with water and smelling of partially burned fuel. You know, condensed crankcase vapors. Preventing this from entering the cylinders is harming my engine how?

Thanks for the pics Sirius. Is that about 3oz you think?

[edcmat-l1]

Why has no one run off that Klingon idiot????

[92rsz]

To the op: I have 3 ls vehicles. All were bone stock when bought with varying mileage. 13k to 130k. I've had all 3 manifolds off at some point. I poured a not small amount of oil out of all 3. Put catch cans on all 3. No more liquid oil in any of them. Always have the milky oil/water mix in the cans like pictured above. Catch cans work

[kingtal0n]

Ok, I think where the problem here is,

Focused on gen3- cute but I am sorry. I've had one LS engine my entire life and its a gen3, yes. But owning a single LS engine in your entire life makes me focused on genX or LS engines? Noooo buddy you got me backwards. I am focused on every engine in the world besides LS. I can't stand LS engines, they are simple but the iron ones are heavy and the aluminum ones in a rationale displacement the 4.8L doesn't exist, how dare they do that to me. I've taken apart plenty of engines but mostly sr20det rb25/26dett 1jz/2jzgte 1zz 3sgte sbc ka20/24 , you know beginner stuff , nice and simple. Because those engines are so old, and development of higher manufacturing was severely limited in the 80's and 90's, the engines are very leaky and blow-by alot more than modern engines do. The crankcase gas mass flow rate is expected to be much lower as years progress. With said mass fraction, there is only one perfect way to eject that mass on any engine, from any manufacturer, of any year or date or model advancement that could ever exist on Earth because it encompass the only correct design by which of course I Mean evacuation of that blow-by gas however minimal, that technique is only done 1 specific way for any engine that ever existed. And I can put numbers on it. Since dissolved gas is based on pressure we want the lowest pressure possible to keep gas out of the liquid oil. That is step #1 crankcase pressure. Next, we have gas mass flow rate. The oil liquids are separated by kinetic energy separation and then the remaining gas is ingested. As the gas cools it begins to condense and will settle on any object between the ejections place (crankcase turns golden brown and dark brown from crankcase gas deposits). We know its a gas because the combustion products ejected from the lower rings and scrapped along the walls was turned into gas. The gas contains carbons which interact with carbons in the engine oil when it dissolves into engine oil, changing the oil structure. Therefore it is imperative to maintain a low pressure for low dissolved gas and to evacuate that gas by separating the liquid oil returned to the oil pan where it cannot react in the presence of water and oxygen and heat. The blow-by gas when evacuated is very hot and could be taken directly from the crankcase into streamlines under a pressure gradient scalar flow and brought back into the combustion chamber from whence they came for round 2 of combustion.

That is the principle for all engines that ever exist to combust gasoline hydrocarbons. How it is done is differently for every engine, yes, but its also tested if the engineers are quality sample and a model is generated. I am pretty sure without checking that chevrolet or gm or whatever tested and modeled the pcv flow for the worst possible conditions otherwise they are not quality or control. Its an untested design. Maybe they are rushed because of EPA. That is the only way they could really screw up some necessary new design and make it OUR responsibility to do something about the poor PCV evacuation which should be capturing and returning that blow-by gas directly back to the chamber. When we finally need to step in and do something to correct for a poor design, our intention should be returning the design to its original intended purpose, that is, rapidly returning combusted blow-by gas to the cylinder. Otherwise, we need to release it or get rid of it somehow. The problem then becomes how to get rid of it if you don't want to ingest it. A vacuum pump can do that. Instead of using the engine as a vacuum pump an external vacuum pump can evacuate and keep pressure down by adjusting input fresh air flow rate and vacuum pump flow rate. But vacuum pumps are maintenance items. We don't want extra maintenance. At this point if you dont mind a electric vacuum pump and monitoring of crankcase pressure this is your best solution for random samples performance engines. Only very high blow-by rate engines will out-flow the electric vacuum pump. Some will even outflow a mechanical pump and still generate pressure in the crankcase. If your engine is one of those then this is when you might need a mechanical vacuum pump absolutely, but that is strict racing with 50 to 60psi of boost for some engines so probably doesn't apply to this forum. But again the solution is the same for all engines but all engines are different so I need to cover every single possibility whether turbo small displacement or na large displacement im doing everything. Now that we've established its not a 50psi of boost racing situations where oil changes and possibly engine rebuilds are just par for the maintenance course. You need some other way to get the blow-by gas out of the crankcase. You already know if you put a breather on the crankcase it will rise scalar pressure and force more contaminants into the engine oil as crankcase pressure rises, defeating your goal of keeping a healthy engine for high mileage. You need to be thinking about that 200,000 mile mark , how the engine will get there. Over time it will need the least amount of combustion products dissolved into engine oil otherwise the carbon deposits accumulate and golden tan turns to dark brown and eventually black and a little piece any day now is gonna block a tiny orifice and trash the engine good. We want to re-use this engine when we hit 300k or 400k or whatever and put some fresh cylinder wall and a new oil pump and go again another 300k. Modern engines past the point of computer modelling and 'copying' among ideal designs everything begins to look the same and engines start to do the same things the same way because the curve for combustion engine technology is a logarithm and we are well into the flatness part of the curve where everyone is sorting out the best thing to do and has copied it for every engine to get the best design at the same time or shortly after. For Chevrolet it was 02' they caught up to Toyota/Nissan from 1995. And notice the two hit the same year for the same implementation of advancements that Chevrolet wouldn't have for a decade, the full package of pan support, coil over plug, seq-efi, metallurgy piston/alloy (same piston materials in a skyline/supra turbo engine from 95) was it a coincidence or just the way things work with a log. The design culture for every combustion engine is a log so obviously everything looks the same once they are ready to be antiquated if the process is done slowly. And how does the handling of combustion products change over time? The only way to evacuate under a negative pressure with mass coming in is to use a pump. The engine is a pump. The products are FROM the combustion chamber so the OEM always uses their current tech to rapidly bring the gas back to the combustion chamber. If the enginers made a mistake and fail quality check then we have to do the same thing. Because its either that or eject it somehow using a vacuum of some kind that is separate from the engine's own provided vacuum pumping action. This is a vacuum pumping problem kids. On turbo engines the vacuum is provided by the turbocharger exhaust gas input energy so the turbo becomes the vacuum pump and the engine is free from that task. But the turbo points directly into the engines air pathway so combustion products still mix back into the combustion chamber but the distance is enormous. From the compressor outlet to the throttle body through an intercooler the combustion gas has to go through there? Do you think any actually make it? They must stick down somewhere. On the way into the compressor outlet or at the outlet or just downstream perhaps they darken the intercooler. What determines where along the intercooler plumbing they will settle down? It asks the temperature. The colder the combustion gas that isn't CO2 or H2O gets, the more it settles down somewhere easily, as it cools. If the design of the chamber is post 92' nissan/toyota or post 02' chevrolet then the products are mostly CO2 and H2O because combustion is very complete on that portion of the log technology curve, its actually ON the visible portion of the curve however because it marks a significant jump in computer modelling and mathematics which have modelled the combustion chemistry and evolution of the flame which converts heat to work. Once they had that out the rest is nickles and dimes on the curve but it still adds up. Direct injection was a tiny jump in comparison but nevertheless makes a contribution and still larger than many others. Which before I digress means that there won't really be much unburnt combustion products in the wot evacuation tune. Actually it means you can remove that tube as periodically inspection and smell and feel for oil or carbon smell to determine the rate of wide open throttle blow-by over time because if something is wrong with the engine and it has blow-by that tube will accumulate some oil and acquire a smell. It is the life line of the engine and should remain dry and supple and smell clean. It is the primary tube of PCV which protects the engine and is the focus of our attention because it indicates engine health and lifespan and diagnostics for problems associated with blow-by. Therefore attaching this tube directly to the turbocharger inlet behind the air filter is a fairly clean and uneventful process where slight oil film develops over the course of 30k 50k 100k miles that may be wiped out or not. I found them at 150k with a sludge in the convolutions of the air filter tube which is easily wiped out. I am told the convolutions are for noise suppression however the fact they catch the sludge so well makes me think oil accumulation control was part of the design plan. That way the turbo only receives a slight misting dose. But again I digress this tube is the wot tube and stays nice and dry if the evacuation is handled at the right pressure. We make that happen by any means necessary even if we need to add a vacuum pump because we have a natural aspirated engine and no turbocharger which means pumping loss is part of driving the PCV system and it consumes around 2 or 5% or whatever of hp to run gasses back to the combustion chamber. This is why breathers increase power. The trade for early ring switching of the piston ring due to high crankcase pressure is worth the energy conserved by not running a PCV system at wide open throttle. This is why people love those breathers boy let me tell you they will do anything for 2% hp even if it means destroying the engine in the process. Accumulation of blow-by products (deposits into oil or onto the engine surfaces directly by gas contact or by interaction between oil with gas and the engine) can be avoided if they are evacuated before they dissolve into engine oil or interact with the engine. Remember we already covered it is a vacuum problem so there must be a vacuum in there somewhere if this is to be achieved and we covered that it is the engine itself pumping loss provides the vacuum, or the turbocharger kinetic energy drive, or a electric or mechanical vacuum pump or exhaust evac. The exhaust evac is fine if you can get it to work and consistent but its rare to see that pulled off well. And that is everything for wot

For the idle of course we have intake suction or a vacuum pump or same things basically. However there are much bigger differences for idle and cruise pcv of course. First of all and most importantly blow-by gas is at a minimum. Secondly the vacuum intake manifold has more stored energy in the form of a vacuum action than we can possible use, so the hose must be metered or the intake manifold will rip the oil seals right out of the engine. The intake manifold fills all of the purposes of a vacuum pump because we don't need the power or demand from the engine, it is at idle/cruise load which is negligible, there is plenty of energy to spare. Therefore there is plenty of energy to drive a kinetic energy separation. You can make the hose longer and add volume and it will still have plenty of vacuum available. If we add a catch can here which many people do then we can separate the oil and air better before returning to the intake manifold and it doesn't hurt the pcv action because we have unlimited vacuum to work with for the job. The mistake people make when they install a catch can on this side of the pcv system is that they think they've installed a catch can. They do not have the experience to understand that catch cans do not belong on that side but that there is no problem if you want to add one there, go for it won't hurt anything. It just doesn't make sense to the people who understand that blow-by is peaking at WOT and WOT is where the trouble is, there shouldn't be any trouble at idle/cruise when things are calmest, rpm is down, blow-by is minimized, windage and circulation is relaxed. Why the hell do you have oil coming out of that side at all? Who puts a catch can on the idle side? Your idle is so rough and terrible that its pushing oil with engine vacuum? They have no idea this is the wrong side to be looking at and worried about on a performance engine. The other side is where I have my nose, I don't even care about the intake suction side because I've got tons of flow I use two 2x supra pcv valves AND a chevrolet pcv valve, on a vertical tube which can easily return driplets of oil to the valve cover if any works its way up, sheesh, its so simple and calm you should never need a catch can on this side. And you tell someone 'you need a catch can' and people talk about it all the damn time and nobody mentions or has a single clue about which side of the pcv system to put a catch can on or what difference it makes, when its literally everything you need understand about pcv and engine operation. At idle and cruise if you are collecting oil at the intake manifold you are doing it wrong and catch cans on this side of the engine are a joke because you could have used a vertical hose leading out of the valve cover instead since the flow is so restricted and the blow-by is so tiny and the conditions are at rest. LOL at you weekend warriors think you are catching oil so proud of the oil collection agency of oil coming from the weakest idle side of the engine, literally at rest just collecting oil. Wake up I'm sorry to do this to you but the catch can goes on the other side of the engine, the other side of the system, and if you start seeing oil there on that side then you are blowing it out of the engine for some reason which is not good. It must be fixed. That line needs to stay bone dry or the engine is sick.