King what year is your C8?

 

I thought the concern expressed by catch can advocates, and those considering one was stated to be build-up of of deposits on the intake valves, ostensibly caused by the what was described as gunk, and in the service manual described as "foul vapor" that is passed into the intake manifold through the tube from the engine block valley. Presumably the question about "oil" in the intake manifold was to suggest that the same stuff that causes deposits on the intake valves also would accumulate in the intake manifold, and somehow be evidence of the need for a catch can. I don't know if any of that is true for the C8, or not, but it's my understanding of the discussion. And for me, the question to be asked is does the"foul vapor" going into the intake manifold contain anything that can cause harmful deposits on the intake valves and if so, does the catch can remove it without harming something else.

 

The C8 has a catch can built into the dry sump. As King explained, tampering with the system can make a good situation bad. The engineers say you don't need it. It's a dumb argument to say "GM's only concerned about the warranty period" like using the car as built is somehow bad for it.

If you don't trust the engineers who built the car to do a decent job of building it, then why buy it? Why do you think the catch can controversy is the only issue. Based on the logic here, these cars (and all cars) should fall completely apart at 5 years. Everything should be failing, not just dirty valves. The lack of critical thinking is amazing. If you're right, it's stupid to buy the car. If you're wrong, then you're wasting money and, even worse, creating a problem.

 

If you understand reaction products of gasoline and oil, if you understand the properties and chemical composition of gasoline and oil, if you understand the science and stereochemistry behind combustion reactants, if you understand the dynamic pressure waves aka 'water hammer' contained with the intake manifold, if you understand overlap, flow work, gas velocity/temperature, scavenging, differential reversion well enough to design your own camshaft profiles, if you understand partial pressure of dissolved gasses and how they influence oil quality, if you understand how piston ring seals and wear patterns depend on 200-800 picometer oil molecules essential to cylinder sealing, if you understand the velocity of gas molecules at rest within a container at STP are moving with statistical variance of roughly 400 to 1000mph, if you understand elastic collision conservation of energy and the influence of impact on oil seals and behavior of oil seals, if you understand how vacuum pumps function in racing practical applications, if you understand how gas density influence collision and occlusion of oil molecule formation, if you understand carbon cycling and sequestration of downstream reaction products & deposition in forming conglomerates and radicals/cations/trash, etc.... &c

I mean this, if you understand how to design, tune, combustion engines for myriad applications in fundamental engineering and chemistry approaches, if you can take any engine in the world whether 2-stroke or 4-stroke and implement electronic or strictly mechanical control,

if you have these type of knowledge and experience and confident in your ability to reverse engineer, debug, decompile the original engineering prospects and applications,

then you can successfully utilize a catch can system on any engine. Although you may realize it is unwanted. A superior design will return oil to the engine sump and keep the oil flowing and warmed throughout the engine, keeping those PCV Products out of the oil as intended and never allowing them to mix. This is the purpose of PCV and leads to engine cleanliness and longevity. These type of devices are called air/oil separators and found on every engine, usually internally. But I Can think of a few examples where they are also found externally such as 89-92 sr20det 2.0L turbo engines.

Otherwise, IMO Leave it alone. You are going to do more harm than good without the knowledge and experience.


This is a chemistry question, a good critical thinking question. You deserve answers.

To answer these questions, I would ask you some questions, 'homework':
-> can you catch gasoline vapors in a can? What about products of gasoline, what are they? What happens when gasoline sits in a can? How about oil?
-> What if we heat oil and gasoline together in a sealed container? Lets say we do this for one week, then two weeks, then three weeks.
What are those products, and as they will enter an engine differently shaped/molecules than the original reactants that we placed in the can in the first place?
What sort of products of gasoline, oil, air are forming over time while heated in a can under various pressure differences?
What about other potential carbon conglomerate forming products, such as pollen, fungus, dust, dirt, etc.... found in air everywhere in the world?

The primary product of combustion is H2O and CO2, but what fraction of fuel and air and oil that enters a modern engine isn't completely reacted and turned into proper products of combustion described previously?

As a chemistry background it is easy to see what products may form, they are myriad constituents. And over time the reactions never end- heating, time, pressure changes, these products react in the presence of water, fuel, oxygen, oil, and change constantly. But I will let you think about these products and whether/which can be stopped in a can type device, or whether they cannot be collected 'foul vapors'. I will say this however: There are three types of materials emanating/involved with an engine, they are Solid, Liquid, and Gas. What causes gasoline to become a gas? What causes oil to become a gas? What sort of reactions are possible while gasoline is a liquid or solid, as opposed to it being a gas?

 

Kling, So no C8? Any corvette?

 

Do you have any updates on the effectiveness of your Catch Can?