So...you don't feel a Catch Can is necessary in a Wet Sump car?!? Check this out
08-04-2015, 02:00 PM
#141
Drifting
So...you don't feel a Catch Can is necessary in a Wet Sump car?!? Check this out
After reading seemingly miles of interesting information here (THANKS) I have made the decision to install a catch can on my Z06 with now 4k miles.
The reasoning for those to hammer me on is..... I DO NOT want any loss of power of the next 10 years. I do not want to walnut blast my heads in 30k miles and then again at 60k. Once at maybe 80k is ok. I DO NOT want to run a cleaner through the engine then create multiple other issues with carbon etc. everywhere. The catch can while fairly inexpensive seems to be a 90% fix to the problem. About every HP engine building I know uses them on NON DI engines what's that say!
To save me from going back does anyone know of the companies that make "good" catch cans for the LT4 that they can list here?
The reasoning for those to hammer me on is..... I DO NOT want any loss of power of the next 10 years. I do not want to walnut blast my heads in 30k miles and then again at 60k. Once at maybe 80k is ok. I DO NOT want to run a cleaner through the engine then create multiple other issues with carbon etc. everywhere. The catch can while fairly inexpensive seems to be a 90% fix to the problem. About every HP engine building I know uses them on NON DI engines what's that say!
To save me from going back does anyone know of the companies that make "good" catch cans for the LT4 that they can list here?
08-04-2015, 07:10 PM
#142
Team Owner
After reading seemingly miles of interesting information here (THANKS) I have made the decision to install a catch can on my Z06 with now 4k miles.
The reasoning for those to hammer me on is..... I DO NOT want any loss of power of the next 10 years. I do not want to walnut blast my heads in 30k miles and then again at 60k. Once at maybe 80k is ok. I DO NOT want to run a cleaner through the engine then create multiple other issues with carbon etc. everywhere. The catch can while fairly inexpensive seems to be a 90% fix to the problem. About every HP engine building I know uses them on NON DI engines what's that say!
To save me from going back does anyone know of the companies that make "good" catch cans for the LT4 that they can list here?
The reasoning for those to hammer me on is..... I DO NOT want any loss of power of the next 10 years. I do not want to walnut blast my heads in 30k miles and then again at 60k. Once at maybe 80k is ok. I DO NOT want to run a cleaner through the engine then create multiple other issues with carbon etc. everywhere. The catch can while fairly inexpensive seems to be a 90% fix to the problem. About every HP engine building I know uses them on NON DI engines what's that say!
To save me from going back does anyone know of the companies that make "good" catch cans for the LT4 that they can list here?
I fought the oil on my 2014. The z06 is not oiling GM made changes and it helped but still is getting crap through. Anything but gas that goes through shows on your exhaust tips. Great place to look to see how the car is running.
The catch can looks to be the ticket I have mine (an E2) and it's going on real soon.
The DI engine is different animal.
08-04-2015, 09:00 PM
#143
Burning Brakes
I fought the oil on my 2014. The z06 is not oiling GM made changes and it helped but still is getting crap through. Anything but gas that goes through shows on your exhaust tips. Great place to look to see how the car is running.
The catch can looks to be the ticket I have mine (an E2) and it's going on real soon.
The DI engine is different animal.
08-05-2015, 03:11 PM
#144
Drifting
Member Since: Feb 2015
Location: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
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Just talked to UPR and they don't make a catch can for the Supercharged LT4... at this time. So Elite is my only choice, figures it sure is expensive compared to others.
08-10-2015, 01:27 PM
#145
Melting Slicks
08-10-2015, 06:40 PM
#147
Melting Slicks
The results are excellent though from those few that helped in the beta testing.
08-10-2015, 08:27 PM
#148
Drifting
Member Since: Feb 2015
Location: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
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After some phone discussion I found GM has a port under the supercharger that is or may be part of their PVC system design. Appears it could allow for block pressure which includes oil vapors and mist to enter the supercharger cavity. From there we all know what happens!
Does anyone out there in LT4 land have anything else to add to this? This hole raises some important questions or maybe not.
1. What was GM's sole purpose of the hole?
2. Does the oil mist help lubricating the supercharger?
3. By installing a can and not addressing the hole are the LT4's only receiving partial can assistance?
4. Has this been discussed with other can companies, Elite?
Does anyone out there in LT4 land have anything else to add to this? This hole raises some important questions or maybe not.
1. What was GM's sole purpose of the hole?
2. Does the oil mist help lubricating the supercharger?
3. By installing a can and not addressing the hole are the LT4's only receiving partial can assistance?
4. Has this been discussed with other can companies, Elite?
08-12-2015, 10:04 AM
#149
Safety Car
Thx Meyerweb. The RX brand and URL has been hi-jacked and they are selling a cheap China knock-off, so the genuine RX designers have halted any RX brands until they can rectify it, so they are suggesting Elite and CoSpeed's newest designs just being released in the next few days so no one gets confused and buys the knock-off's.
The results are excellent though from those few that helped in the beta testing.
The results are excellent though from those few that helped in the beta testing.
RX products may have been copied, I don't know, but you can contact the real company here: RXProducts@aol.com and they are alive and well in Florida, still developing their products.
08-12-2015, 10:10 AM
#150
I'm Batman..
Pro Mechanic
Thread Starter
Member Since: Apr 2014
Location: Lehigh Acres FL
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Since I am going with a blower in the next couple weeks I opted to upgrade from my Elite Engineering can and get the LMR can. I got a good deal on a used one off here that I could not turn down. (I tried to turn it down, and I couldn't let myself do it lol). The tank is the first release so it has to get updated to the new revision so I sent it off to LMR last week for the update. They advised $200 for the update and they will weld the new fittings on the back of the tank and supply the proper hoses for rerouting the fumes. They are also supposed to be including all new lines with the quick connect fittings for the valve covers. I am hoping they call me any day now to get payment and tell me it's ready to ship out. 
08-12-2015, 11:14 AM
#151
Burning Brakes
This is BS, and you know it. You even PM'd me accurate information, but persist in telling lies on the forum. I know one company I don't trust, and it's not RX.
RX products may have been copied, I don't know, but you can contact the real company here: RXProducts@aol.com and they are alive and well in Florida, still developing their products.
RX products may have been copied, I don't know, but you can contact the real company here: RXProducts@aol.com and they are alive and well in Florida, still developing their products.
08-12-2015, 01:53 PM
#152
Safety Car
meyerweb---I was the primary beta tester. Yes it is true. Lot's going on behind the scenes but coSpeed2 is telling the truth. There is legal actions being taken. coSpeed2 has the same can that the Real RX company developed. I have been to his shop more than once in Florida. You can rest easy.
08-13-2015, 07:58 PM
#153
Melting Slicks
The Chinese counterfeits even have the RevXtreme and related URL's. They are only moving some stock out. We used to sell the heck out of them and are sad to see this as well.
08-13-2015, 11:23 PM
#154
Team Owner
Member Since: Jan 2007
Location: cookeville tennessee
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you are introducing unmetered air into your engine and screwing up your fueling. this was a great idea in the late 90s and then with the early C5 days when we didn't know better.
if you put filters on your valve covers you need to plug all other pcv ports, you are just pulling air through the crankcase into your intake manifold from the filters. bad idea.
vacuum pump is a great idea, I ran www.gzmotorsports.com on my C5Z with great success but not one available yet for an LT1 since they need to mount on the opposite side.
if you put filters on your valve covers you need to plug all other pcv ports, you are just pulling air through the crankcase into your intake manifold from the filters. bad idea.
vacuum pump is a great idea, I ran www.gzmotorsports.com on my C5Z with great success but not one available yet for an LT1 since they need to mount on the opposite side.
I had this same set up on my c5 RHS 427 F1X blower motor pushing almost 1200 rwhp, & with only 4300 miles on it the heads look like ****. Motor looked like it had 100,k miles on it.
08-14-2015, 02:19 AM
#155
Melting Slicks
water is in our atmosphere, and is also a byproduct of combustion. When an engine sits overnight, the atmosphere will undoubtedly bring some of this water into the crankcase. Blow-by, which all engines produce to some degree, will also allow water into the crank case, since blow-by undoubtedly contains water (and many other assorted more or less carbon based combustion by-product).
When the engine reaches operating temperature (When the oil hits 200-212*F~) the water can no longer stay in the oil, or near it. So it does what all water does, and becomes as a gas as much as possible trying to escape the hot engine oil (as opposed to when the oil was cold, the water did not mind being near the oil so much, and may be found collecting (condensing) on surfaces nearby or even in the oil itself (if you pour water into oil, it will sink to the bottom of the oil))
The PCV system, when functioning properly, helps to also reduce the boiling point of water (water under any vacuum with respect to the atmosphere will evaporate at lower temperature, imagine higher altitudes where pressure is lower as a good example) this water and blow-by gasses are sucked into the PCV system (which is tied to the intake manifold one way or the other) and burnt harmlessly. Water you may find "collected" and "condensed" inside a catch can that you have added yourself, to the PCV system, and thought "wow! better here than in my engine!" would have simply been burnt off harmlessly as intended by the factory PCV design (the engineers know all about water molecules and partial pressures), and plays no role in any deleterious effect on any engine.
The stronger the vacuum in the crank case (imagine you run a vacuum pump) the more effective the PCV will be at removing water and blow-by gasses from the crank case. Run a strong enough vacuum and you will also pull in your oil seals, so, the application of the engine (did you prepare your oil seals while building the engine for such strong vacuum? some do) will determine what sort of vacuum differential you are able to apply to your engine. A stronger vacuum in the crank case is associated with increased power output as an added benefit (besides simply removing blow-by gasses and water)
Now, what causes oil to leave the crankcase to begin with? There have been some good analogies already (a strong hurricane force wind) and good examples (poor ring seal, poor cylinder roundness) of how this occurs. I want to add to these with my own short example to further the subject.
If you ever removed the valvecover of an engine while it was running you may have noticed that oil is thrown everywhere. Since the crankcase need to breath somewhere, The valvecover is typically considered the best place for such a hole to exist, and it contains a baffle, a carefully constructed passage, through which this whipping flurry of engine oil is soothed and contained, allowed to drain back to the engine as much as possible, allowing for crankcase gasses to exit without carrying so much liquid oil along for the ride. A well constructed valve cover baffle will lower the quantity of oil exiting the crankcase via the PCV port to near nothing, as intended by the factory when it was designed, although some seems to escape no matter what. As blow-by (cylinder leakdown %) increases, either due to poor ring seal or misshapen cylinder walls or fried piston rings or other reasons, there becomes now more force behind this whipping flurry of engine oil that assists in driving out the liquid state of oil past the baffle of the valvecover, which was only intended to deal with up to a specific amount of blow-by from the factory.
How do we deal with excessive blow-by that is forcing liquid oil from the crankcase, past the OEM baffle which can no longer contain it? First you need to realize that on an OEM engine, this is a sign that something is wrong, if liquid oil in any sufficient quantity is able to pass the OEM baffle enough to raise an eyebrow, it indicates that there is a serious problem with perhaps a piston ring(s), or a cylinder malformation, and the only truly corrective measure is to take the engine apart and fix the cylinder wall or replace the piston rings, to deal with the problem at its source.
In other cases, maybe you simply removed the OEM baffle without realizing how important it was, or maybe you installed some enormously gapped piston rings with huge piston/wall clearances and expected an increase in blow-by gas because you wanted to produce 2X00horsepower and didn't want to seize a piston up in the bore at 9,200rpm when you made that X second pass. Depending on the engine, sometimes simply raising the RPM limiter is enough to start seeing engine oil pass the baffle (rpm certain directly influences the whipping/flurry action of oil) so really it depends on the engine in discussion and the application, as to whether or not the oil escaping the crankcase is "normal" or not.
That point made, the only thing you can really do to deal with that oil, is try to catch it (catch-cans), and prevent it from going someplace undesirable (into your intake manifold or all over the engine bay for example) and then either return it right back into the engine or have it sit in a container somewhere until you get a chance to empty it. I wish to re-emphasize, how an OEM engine should never see any significant passage of liquid oil (unless it becomes a well known fact that a particular engine has a poorly designed OEM baffle) and that this would generally indicate a problem as described above.
and last here are a few fun facts about oil and pcv,
1. engines that make only short trips, and whos oil rarely reaches operating temperature (200-212*F at least) typically experience excessive wear and tear. The same is true for engines that are operated with cold water, such as when the owner removed the thermostat or installs a colder value (130-150*F) seeking performance boost.
2. oil that makes it way into the combustion chamber increases the compression ratio there and is associated with pre-ignition or detonation problems.
3. water injection is associated with a "steam cleaning effect" that will typically result with cleaner piston surfaces, and reduced carbon build-up. However, this should not be seen as a band-aid for an improperly functioning pcv system.
4. Although not environmentally friendly, exhaust driven and vacuum pump driven pcv systems are considered the safest way to dispose of combustion by-product gasses from the crank case, as neither will allow these gasses to pass back into the combustion chamber if designed properly.
When the engine reaches operating temperature (When the oil hits 200-212*F~) the water can no longer stay in the oil, or near it. So it does what all water does, and becomes as a gas as much as possible trying to escape the hot engine oil (as opposed to when the oil was cold, the water did not mind being near the oil so much, and may be found collecting (condensing) on surfaces nearby or even in the oil itself (if you pour water into oil, it will sink to the bottom of the oil))
The PCV system, when functioning properly, helps to also reduce the boiling point of water (water under any vacuum with respect to the atmosphere will evaporate at lower temperature, imagine higher altitudes where pressure is lower as a good example) this water and blow-by gasses are sucked into the PCV system (which is tied to the intake manifold one way or the other) and burnt harmlessly. Water you may find "collected" and "condensed" inside a catch can that you have added yourself, to the PCV system, and thought "wow! better here than in my engine!" would have simply been burnt off harmlessly as intended by the factory PCV design (the engineers know all about water molecules and partial pressures), and plays no role in any deleterious effect on any engine.
The stronger the vacuum in the crank case (imagine you run a vacuum pump) the more effective the PCV will be at removing water and blow-by gasses from the crank case. Run a strong enough vacuum and you will also pull in your oil seals, so, the application of the engine (did you prepare your oil seals while building the engine for such strong vacuum? some do) will determine what sort of vacuum differential you are able to apply to your engine. A stronger vacuum in the crank case is associated with increased power output as an added benefit (besides simply removing blow-by gasses and water)
Now, what causes oil to leave the crankcase to begin with? There have been some good analogies already (a strong hurricane force wind) and good examples (poor ring seal, poor cylinder roundness) of how this occurs. I want to add to these with my own short example to further the subject.
If you ever removed the valvecover of an engine while it was running you may have noticed that oil is thrown everywhere. Since the crankcase need to breath somewhere, The valvecover is typically considered the best place for such a hole to exist, and it contains a baffle, a carefully constructed passage, through which this whipping flurry of engine oil is soothed and contained, allowed to drain back to the engine as much as possible, allowing for crankcase gasses to exit without carrying so much liquid oil along for the ride. A well constructed valve cover baffle will lower the quantity of oil exiting the crankcase via the PCV port to near nothing, as intended by the factory when it was designed, although some seems to escape no matter what. As blow-by (cylinder leakdown %) increases, either due to poor ring seal or misshapen cylinder walls or fried piston rings or other reasons, there becomes now more force behind this whipping flurry of engine oil that assists in driving out the liquid state of oil past the baffle of the valvecover, which was only intended to deal with up to a specific amount of blow-by from the factory.
How do we deal with excessive blow-by that is forcing liquid oil from the crankcase, past the OEM baffle which can no longer contain it? First you need to realize that on an OEM engine, this is a sign that something is wrong, if liquid oil in any sufficient quantity is able to pass the OEM baffle enough to raise an eyebrow, it indicates that there is a serious problem with perhaps a piston ring(s), or a cylinder malformation, and the only truly corrective measure is to take the engine apart and fix the cylinder wall or replace the piston rings, to deal with the problem at its source.
In other cases, maybe you simply removed the OEM baffle without realizing how important it was, or maybe you installed some enormously gapped piston rings with huge piston/wall clearances and expected an increase in blow-by gas because you wanted to produce 2X00horsepower and didn't want to seize a piston up in the bore at 9,200rpm when you made that X second pass. Depending on the engine, sometimes simply raising the RPM limiter is enough to start seeing engine oil pass the baffle (rpm certain directly influences the whipping/flurry action of oil) so really it depends on the engine in discussion and the application, as to whether or not the oil escaping the crankcase is "normal" or not.
That point made, the only thing you can really do to deal with that oil, is try to catch it (catch-cans), and prevent it from going someplace undesirable (into your intake manifold or all over the engine bay for example) and then either return it right back into the engine or have it sit in a container somewhere until you get a chance to empty it. I wish to re-emphasize, how an OEM engine should never see any significant passage of liquid oil (unless it becomes a well known fact that a particular engine has a poorly designed OEM baffle) and that this would generally indicate a problem as described above.
and last here are a few fun facts about oil and pcv,
1. engines that make only short trips, and whos oil rarely reaches operating temperature (200-212*F at least) typically experience excessive wear and tear. The same is true for engines that are operated with cold water, such as when the owner removed the thermostat or installs a colder value (130-150*F) seeking performance boost.
2. oil that makes it way into the combustion chamber increases the compression ratio there and is associated with pre-ignition or detonation problems.
3. water injection is associated with a "steam cleaning effect" that will typically result with cleaner piston surfaces, and reduced carbon build-up. However, this should not be seen as a band-aid for an improperly functioning pcv system.
4. Although not environmentally friendly, exhaust driven and vacuum pump driven pcv systems are considered the safest way to dispose of combustion by-product gasses from the crank case, as neither will allow these gasses to pass back into the combustion chamber if designed properly.
Last edited by Kingtal0n; 08-14-2015 at 02:32 AM.
08-14-2015, 07:24 AM
#156
I'm Batman..
Pro Mechanic
Thread Starter
Member Since: Apr 2014
Location: Lehigh Acres FL
Posts: 6,130
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water is in our atmosphere, and is also a byproduct of combustion. When an engine sits overnight, the atmosphere will undoubtedly bring some of this water into the crankcase. Blow-by, which all engines produce to some degree, will also allow water into the crank case, since blow-by undoubtedly contains water (and many other assorted more or less carbon based combustion by-product).
When the engine reaches operating temperature (When the oil hits 200-212*F~) the water can no longer stay in the oil, or near it. So it does what all water does, and becomes as a gas as much as possible trying to escape the hot engine oil (as opposed to when the oil was cold, the water did not mind being near the oil so much, and may be found collecting (condensing) on surfaces nearby or even in the oil itself (if you pour water into oil, it will sink to the bottom of the oil))
The PCV system, when functioning properly, helps to also reduce the boiling point of water (water under any vacuum with respect to the atmosphere will evaporate at lower temperature, imagine higher altitudes where pressure is lower as a good example) this water and blow-by gasses are sucked into the PCV system (which is tied to the intake manifold one way or the other) and burnt harmlessly. Water you may find "collected" and "condensed" inside a catch can that you have added yourself, to the PCV system, and thought "wow! better here than in my engine!" would have simply been burnt off harmlessly as intended by the factory PCV design (the engineers know all about water molecules and partial pressures), and plays no role in any deleterious effect on any engine.
The stronger the vacuum in the crank case (imagine you run a vacuum pump) the more effective the PCV will be at removing water and blow-by gasses from the crank case. Run a strong enough vacuum and you will also pull in your oil seals, so, the application of the engine (did you prepare your oil seals while building the engine for such strong vacuum? some do) will determine what sort of vacuum differential you are able to apply to your engine. A stronger vacuum in the crank case is associated with increased power output as an added benefit (besides simply removing blow-by gasses and water)
Now, what causes oil to leave the crankcase to begin with? There have been some good analogies already (a strong hurricane force wind) and good examples (poor ring seal, poor cylinder roundness) of how this occurs. I want to add to these with my own short example to further the subject.
If you ever removed the valvecover of an engine while it was running you may have noticed that oil is thrown everywhere. Since the crankcase need to breath somewhere, The valvecover is typically considered the best place for such a hole to exist, and it contains a baffle, a carefully constructed passage, through which this whipping flurry of engine oil is soothed and contained, allowed to drain back to the engine as much as possible, allowing for crankcase gasses to exit without carrying so much liquid oil along for the ride. A well constructed valve cover baffle will lower the quantity of oil exiting the crankcase via the PCV port to near nothing, as intended by the factory when it was designed, although some seems to escape no matter what. As blow-by (cylinder leakdown %) increases, either due to poor ring seal or misshapen cylinder walls or fried piston rings or other reasons, there becomes now more force behind this whipping flurry of engine oil that assists in driving out the liquid state of oil past the baffle of the valvecover, which was only intended to deal with up to a specific amount of blow-by from the factory.
How do we deal with excessive blow-by that is forcing liquid oil from the crankcase, past the OEM baffle which can no longer contain it? First you need to realize that on an OEM engine, this is a sign that something is wrong, if liquid oil in any sufficient quantity is able to pass the OEM baffle enough to raise an eyebrow, it indicates that there is a serious problem with perhaps a piston ring(s), or a cylinder malformation, and the only truly corrective measure is to take the engine apart and fix the cylinder wall or replace the piston rings, to deal with the problem at its source.
In other cases, maybe you simply removed the OEM baffle without realizing how important it was, or maybe you installed some enormously gapped piston rings with huge piston/wall clearances and expected an increase in blow-by gas because you wanted to produce 2X00horsepower and didn't want to seize a piston up in the bore at 9,200rpm when you made that X second pass. Depending on the engine, sometimes simply raising the RPM limiter is enough to start seeing engine oil pass the baffle (rpm certain directly influences the whipping/flurry action of oil) so really it depends on the engine in discussion and the application, as to whether or not the oil escaping the crankcase is "normal" or not.
That point made, the only thing you can really do to deal with that oil, is try to catch it (catch-cans), and prevent it from going someplace undesirable (into your intake manifold or all over the engine bay for example) and then either return it right back into the engine or have it sit in a container somewhere until you get a chance to empty it. I wish to re-emphasize, how an OEM engine should never see any significant passage of liquid oil (unless it becomes a well known fact that a particular engine has a poorly designed OEM baffle) and that this would generally indicate a problem as described above.
and last here are a few fun facts about oil and pcv,
1. engines that make only short trips, and whos oil rarely reaches operating temperature (200-212*F at least) typically experience excessive wear and tear. The same is true for engines that are operated with cold water, such as when the owner removed the thermostat or installs a colder value (130-150*F) seeking performance boost.
2. oil that makes it way into the combustion chamber increases the compression ratio there and is associated with pre-ignition or detonation problems.
3. water injection is associated with a "steam cleaning effect" that will typically result with cleaner piston surfaces, and reduced carbon build-up. However, this should not be seen as a band-aid for an improperly functioning pcv system.
4. Although not environmentally friendly, exhaust driven and vacuum pump driven pcv systems are considered the safest way to dispose of combustion by-product gasses from the crank case, as neither will allow these gasses to pass back into the combustion chamber if designed properly.
When the engine reaches operating temperature (When the oil hits 200-212*F~) the water can no longer stay in the oil, or near it. So it does what all water does, and becomes as a gas as much as possible trying to escape the hot engine oil (as opposed to when the oil was cold, the water did not mind being near the oil so much, and may be found collecting (condensing) on surfaces nearby or even in the oil itself (if you pour water into oil, it will sink to the bottom of the oil))
The PCV system, when functioning properly, helps to also reduce the boiling point of water (water under any vacuum with respect to the atmosphere will evaporate at lower temperature, imagine higher altitudes where pressure is lower as a good example) this water and blow-by gasses are sucked into the PCV system (which is tied to the intake manifold one way or the other) and burnt harmlessly. Water you may find "collected" and "condensed" inside a catch can that you have added yourself, to the PCV system, and thought "wow! better here than in my engine!" would have simply been burnt off harmlessly as intended by the factory PCV design (the engineers know all about water molecules and partial pressures), and plays no role in any deleterious effect on any engine.
The stronger the vacuum in the crank case (imagine you run a vacuum pump) the more effective the PCV will be at removing water and blow-by gasses from the crank case. Run a strong enough vacuum and you will also pull in your oil seals, so, the application of the engine (did you prepare your oil seals while building the engine for such strong vacuum? some do) will determine what sort of vacuum differential you are able to apply to your engine. A stronger vacuum in the crank case is associated with increased power output as an added benefit (besides simply removing blow-by gasses and water)
Now, what causes oil to leave the crankcase to begin with? There have been some good analogies already (a strong hurricane force wind) and good examples (poor ring seal, poor cylinder roundness) of how this occurs. I want to add to these with my own short example to further the subject.
If you ever removed the valvecover of an engine while it was running you may have noticed that oil is thrown everywhere. Since the crankcase need to breath somewhere, The valvecover is typically considered the best place for such a hole to exist, and it contains a baffle, a carefully constructed passage, through which this whipping flurry of engine oil is soothed and contained, allowed to drain back to the engine as much as possible, allowing for crankcase gasses to exit without carrying so much liquid oil along for the ride. A well constructed valve cover baffle will lower the quantity of oil exiting the crankcase via the PCV port to near nothing, as intended by the factory when it was designed, although some seems to escape no matter what. As blow-by (cylinder leakdown %) increases, either due to poor ring seal or misshapen cylinder walls or fried piston rings or other reasons, there becomes now more force behind this whipping flurry of engine oil that assists in driving out the liquid state of oil past the baffle of the valvecover, which was only intended to deal with up to a specific amount of blow-by from the factory.
How do we deal with excessive blow-by that is forcing liquid oil from the crankcase, past the OEM baffle which can no longer contain it? First you need to realize that on an OEM engine, this is a sign that something is wrong, if liquid oil in any sufficient quantity is able to pass the OEM baffle enough to raise an eyebrow, it indicates that there is a serious problem with perhaps a piston ring(s), or a cylinder malformation, and the only truly corrective measure is to take the engine apart and fix the cylinder wall or replace the piston rings, to deal with the problem at its source.
In other cases, maybe you simply removed the OEM baffle without realizing how important it was, or maybe you installed some enormously gapped piston rings with huge piston/wall clearances and expected an increase in blow-by gas because you wanted to produce 2X00horsepower and didn't want to seize a piston up in the bore at 9,200rpm when you made that X second pass. Depending on the engine, sometimes simply raising the RPM limiter is enough to start seeing engine oil pass the baffle (rpm certain directly influences the whipping/flurry action of oil) so really it depends on the engine in discussion and the application, as to whether or not the oil escaping the crankcase is "normal" or not.
That point made, the only thing you can really do to deal with that oil, is try to catch it (catch-cans), and prevent it from going someplace undesirable (into your intake manifold or all over the engine bay for example) and then either return it right back into the engine or have it sit in a container somewhere until you get a chance to empty it. I wish to re-emphasize, how an OEM engine should never see any significant passage of liquid oil (unless it becomes a well known fact that a particular engine has a poorly designed OEM baffle) and that this would generally indicate a problem as described above.
and last here are a few fun facts about oil and pcv,
1. engines that make only short trips, and whos oil rarely reaches operating temperature (200-212*F at least) typically experience excessive wear and tear. The same is true for engines that are operated with cold water, such as when the owner removed the thermostat or installs a colder value (130-150*F) seeking performance boost.
2. oil that makes it way into the combustion chamber increases the compression ratio there and is associated with pre-ignition or detonation problems.
3. water injection is associated with a "steam cleaning effect" that will typically result with cleaner piston surfaces, and reduced carbon build-up. However, this should not be seen as a band-aid for an improperly functioning pcv system.
4. Although not environmentally friendly, exhaust driven and vacuum pump driven pcv systems are considered the safest way to dispose of combustion by-product gasses from the crank case, as neither will allow these gasses to pass back into the combustion chamber if designed properly.
Good info! One of the big challenges we C7 owners face through all of this is when excessive oil ingestion is experienced, (resulting in an eyebrow raising moment when emptying a catch can) GM does not want to start tearing engines apart to fix the issue. Proof of this can be basically seen as when you complain of this at the dealer they require you to take an "oil consumption test" where you log the oil level on the dipstick over the course of 5000 miles or so. Thats all and great but the issue I have with that is they clearly put on the document that consumption (burning OR ingestion) of a 1 quart of oil per 500 miles when the vehicle is used for hard acceleration is "NORMAL". I'm sure we can all agree to disagree with them on that. Its downright stomach turning that they consider that much oil loss "NORMAL" 
Ant
08-15-2015, 04:42 PM
#157
Melting Slicks
water is in our atmosphere, and is also a byproduct of combustion. When an engine sits overnight, the atmosphere will undoubtedly bring some of this water into the crankcase. Blow-by, which all engines produce to some degree, will also allow water into the crank case, since blow-by undoubtedly contains water (and many other assorted more or less carbon based combustion by-product).
When the engine reaches operating temperature (When the oil hits 200-212*F~) the water can no longer stay in the oil, or near it. So it does what all water does, and becomes as a gas as much as possible trying to escape the hot engine oil (as opposed to when the oil was cold, the water did not mind being near the oil so much, and may be found collecting (condensing) on surfaces nearby or even in the oil itself (if you pour water into oil, it will sink to the bottom of the oil))
The PCV system, when functioning properly, helps to also reduce the boiling point of water (water under any vacuum with respect to the atmosphere will evaporate at lower temperature, imagine higher altitudes where pressure is lower as a good example) this water and blow-by gasses are sucked into the PCV system (which is tied to the intake manifold one way or the other) and burnt harmlessly. Water you may find "collected" and "condensed" inside a catch can that you have added yourself, to the PCV system, and thought "wow! better here than in my engine!" would have simply been burnt off harmlessly as intended by the factory PCV design (the engineers know all about water molecules and partial pressures), and plays no role in any deleterious effect on any engine.
The stronger the vacuum in the crank case (imagine you run a vacuum pump) the more effective the PCV will be at removing water and blow-by gasses from the crank case. Run a strong enough vacuum and you will also pull in your oil seals, so, the application of the engine (did you prepare your oil seals while building the engine for such strong vacuum? some do) will determine what sort of vacuum differential you are able to apply to your engine. A stronger vacuum in the crank case is associated with increased power output as an added benefit (besides simply removing blow-by gasses and water)
Now, what causes oil to leave the crankcase to begin with? There have been some good analogies already (a strong hurricane force wind) and good examples (poor ring seal, poor cylinder roundness) of how this occurs. I want to add to these with my own short example to further the subject.
If you ever removed the valvecover of an engine while it was running you may have noticed that oil is thrown everywhere. Since the crankcase need to breath somewhere, The valvecover is typically considered the best place for such a hole to exist, and it contains a baffle, a carefully constructed passage, through which this whipping flurry of engine oil is soothed and contained, allowed to drain back to the engine as much as possible, allowing for crankcase gasses to exit without carrying so much liquid oil along for the ride. A well constructed valve cover baffle will lower the quantity of oil exiting the crankcase via the PCV port to near nothing, as intended by the factory when it was designed, although some seems to escape no matter what. As blow-by (cylinder leakdown %) increases, either due to poor ring seal or misshapen cylinder walls or fried piston rings or other reasons, there becomes now more force behind this whipping flurry of engine oil that assists in driving out the liquid state of oil past the baffle of the valvecover, which was only intended to deal with up to a specific amount of blow-by from the factory.
How do we deal with excessive blow-by that is forcing liquid oil from the crankcase, past the OEM baffle which can no longer contain it? First you need to realize that on an OEM engine, this is a sign that something is wrong, if liquid oil in any sufficient quantity is able to pass the OEM baffle enough to raise an eyebrow, it indicates that there is a serious problem with perhaps a piston ring(s), or a cylinder malformation, and the only truly corrective measure is to take the engine apart and fix the cylinder wall or replace the piston rings, to deal with the problem at its source.
In other cases, maybe you simply removed the OEM baffle without realizing how important it was, or maybe you installed some enormously gapped piston rings with huge piston/wall clearances and expected an increase in blow-by gas because you wanted to produce 2X00horsepower and didn't want to seize a piston up in the bore at 9,200rpm when you made that X second pass. Depending on the engine, sometimes simply raising the RPM limiter is enough to start seeing engine oil pass the baffle (rpm certain directly influences the whipping/flurry action of oil) so really it depends on the engine in discussion and the application, as to whether or not the oil escaping the crankcase is "normal" or not.
That point made, the only thing you can really do to deal with that oil, is try to catch it (catch-cans), and prevent it from going someplace undesirable (into your intake manifold or all over the engine bay for example) and then either return it right back into the engine or have it sit in a container somewhere until you get a chance to empty it. I wish to re-emphasize, how an OEM engine should never see any significant passage of liquid oil (unless it becomes a well known fact that a particular engine has a poorly designed OEM baffle) and that this would generally indicate a problem as described above.
and last here are a few fun facts about oil and pcv,
1. engines that make only short trips, and whos oil rarely reaches operating temperature (200-212*F at least) typically experience excessive wear and tear. The same is true for engines that are operated with cold water, such as when the owner removed the thermostat or installs a colder value (130-150*F) seeking performance boost.
2. oil that makes it way into the combustion chamber increases the compression ratio there and is associated with pre-ignition or detonation problems.
3. water injection is associated with a "steam cleaning effect" that will typically result with cleaner piston surfaces, and reduced carbon build-up. However, this should not be seen as a band-aid for an improperly functioning pcv system.
4. Although not environmentally friendly, exhaust driven and vacuum pump driven pcv systems are considered the safest way to dispose of combustion by-product gasses from the crank case, as neither will allow these gasses to pass back into the combustion chamber if designed properly.
When the engine reaches operating temperature (When the oil hits 200-212*F~) the water can no longer stay in the oil, or near it. So it does what all water does, and becomes as a gas as much as possible trying to escape the hot engine oil (as opposed to when the oil was cold, the water did not mind being near the oil so much, and may be found collecting (condensing) on surfaces nearby or even in the oil itself (if you pour water into oil, it will sink to the bottom of the oil))
The PCV system, when functioning properly, helps to also reduce the boiling point of water (water under any vacuum with respect to the atmosphere will evaporate at lower temperature, imagine higher altitudes where pressure is lower as a good example) this water and blow-by gasses are sucked into the PCV system (which is tied to the intake manifold one way or the other) and burnt harmlessly. Water you may find "collected" and "condensed" inside a catch can that you have added yourself, to the PCV system, and thought "wow! better here than in my engine!" would have simply been burnt off harmlessly as intended by the factory PCV design (the engineers know all about water molecules and partial pressures), and plays no role in any deleterious effect on any engine.
The stronger the vacuum in the crank case (imagine you run a vacuum pump) the more effective the PCV will be at removing water and blow-by gasses from the crank case. Run a strong enough vacuum and you will also pull in your oil seals, so, the application of the engine (did you prepare your oil seals while building the engine for such strong vacuum? some do) will determine what sort of vacuum differential you are able to apply to your engine. A stronger vacuum in the crank case is associated with increased power output as an added benefit (besides simply removing blow-by gasses and water)
Now, what causes oil to leave the crankcase to begin with? There have been some good analogies already (a strong hurricane force wind) and good examples (poor ring seal, poor cylinder roundness) of how this occurs. I want to add to these with my own short example to further the subject.
If you ever removed the valvecover of an engine while it was running you may have noticed that oil is thrown everywhere. Since the crankcase need to breath somewhere, The valvecover is typically considered the best place for such a hole to exist, and it contains a baffle, a carefully constructed passage, through which this whipping flurry of engine oil is soothed and contained, allowed to drain back to the engine as much as possible, allowing for crankcase gasses to exit without carrying so much liquid oil along for the ride. A well constructed valve cover baffle will lower the quantity of oil exiting the crankcase via the PCV port to near nothing, as intended by the factory when it was designed, although some seems to escape no matter what. As blow-by (cylinder leakdown %) increases, either due to poor ring seal or misshapen cylinder walls or fried piston rings or other reasons, there becomes now more force behind this whipping flurry of engine oil that assists in driving out the liquid state of oil past the baffle of the valvecover, which was only intended to deal with up to a specific amount of blow-by from the factory.
How do we deal with excessive blow-by that is forcing liquid oil from the crankcase, past the OEM baffle which can no longer contain it? First you need to realize that on an OEM engine, this is a sign that something is wrong, if liquid oil in any sufficient quantity is able to pass the OEM baffle enough to raise an eyebrow, it indicates that there is a serious problem with perhaps a piston ring(s), or a cylinder malformation, and the only truly corrective measure is to take the engine apart and fix the cylinder wall or replace the piston rings, to deal with the problem at its source.
In other cases, maybe you simply removed the OEM baffle without realizing how important it was, or maybe you installed some enormously gapped piston rings with huge piston/wall clearances and expected an increase in blow-by gas because you wanted to produce 2X00horsepower and didn't want to seize a piston up in the bore at 9,200rpm when you made that X second pass. Depending on the engine, sometimes simply raising the RPM limiter is enough to start seeing engine oil pass the baffle (rpm certain directly influences the whipping/flurry action of oil) so really it depends on the engine in discussion and the application, as to whether or not the oil escaping the crankcase is "normal" or not.
That point made, the only thing you can really do to deal with that oil, is try to catch it (catch-cans), and prevent it from going someplace undesirable (into your intake manifold or all over the engine bay for example) and then either return it right back into the engine or have it sit in a container somewhere until you get a chance to empty it. I wish to re-emphasize, how an OEM engine should never see any significant passage of liquid oil (unless it becomes a well known fact that a particular engine has a poorly designed OEM baffle) and that this would generally indicate a problem as described above.
and last here are a few fun facts about oil and pcv,
1. engines that make only short trips, and whos oil rarely reaches operating temperature (200-212*F at least) typically experience excessive wear and tear. The same is true for engines that are operated with cold water, such as when the owner removed the thermostat or installs a colder value (130-150*F) seeking performance boost.
2. oil that makes it way into the combustion chamber increases the compression ratio there and is associated with pre-ignition or detonation problems.
3. water injection is associated with a "steam cleaning effect" that will typically result with cleaner piston surfaces, and reduced carbon build-up. However, this should not be seen as a band-aid for an improperly functioning pcv system.
4. Although not environmentally friendly, exhaust driven and vacuum pump driven pcv systems are considered the safest way to dispose of combustion by-product gasses from the crank case, as neither will allow these gasses to pass back into the combustion chamber if designed properly.
Excellent contribution King!, but only a few things to correct. When this water enters the crankcase as blow-by it mixes with various hydrocarbon based compounds and creates sulfuric acid. When the engine reaches the temps you correctly list for this to happen, much of it can "flash off" but only a portion, and since most are installing 160-180* thermostats they will not be at the temps needed for an effective (as you also correctly mention). And none of the other damaging compounds will flash back off and are in the oil until changed.
Then the header collector evac's can only work with a no muffler zero restriction exhaust or you will see the diaphragms blow from back-pressure, so they work somewhat well on race applications, but not street. And finally, a belt driven vacuum pump is far and away the best solution period, but no pump, Moroso, Aerospace Components, GZ, etc. will last more than 5k or so miles on the street without having to replace the vanes, bearings, seals and most times the shaft from the wear caused. Great for track use though.
Water injection will never be enough as the intake valves are running so hot these compounds bake on near instantly, and they bake on hard vs the old carbureted and port injection where it did remove light carbon effectively. That and filling the reservoir many will balk at, but all great points you made.
Then the oil ingestion does raise comp causing detonation, but it also contaminates that air/fuel mixture reducing usable octane and releasing less energy (power) and thus less MPG.
Another excellent contributor!!! Stay in these threads, we need more that understand this!
Good info! One of the big challenges we C7 owners face through all of this is when excessive oil ingestion is experienced, (resulting in an eyebrow raising moment when emptying a catch can) GM does not want to start tearing engines apart to fix the issue. Proof of this can be basically seen as when you complain of this at the dealer they require you to take an "oil consumption test" where you log the oil level on the dipstick over the course of 5000 miles or so. Thats all and great but the issue I have with that is they clearly put on the document that consumption (burning OR ingestion) of a 1 quart of oil per 500 miles when the vehicle is used for hard acceleration is "NORMAL". I'm sure we can all agree to disagree with them on that. Its downright stomach turning that they consider that much oil loss "NORMAL" Ant
Two great contributors with knowledge VS assumptions or quoting PR releases!!
Last edited by COSPEED; 08-15-2015 at 04:47 PM.
08-16-2015, 08:54 AM
#158
After some phone discussion I found GM has a port under the supercharger that is or may be part of their PVC system design. Appears it could allow for block pressure which includes oil vapors and mist to enter the supercharger cavity. From there we all know what happens!
Does anyone out there in LT4 land have anything else to add to this? This hole raises some important questions or maybe not.
1. What was GM's sole purpose of the hole?
2. Does the oil mist help lubricating the supercharger?
3. By installing a can and not addressing the hole are the LT4's only receiving partial can assistance?
4. Has this been discussed with other can companies, Elite?
Does anyone out there in LT4 land have anything else to add to this? This hole raises some important questions or maybe not.
1. What was GM's sole purpose of the hole?
2. Does the oil mist help lubricating the supercharger?
3. By installing a can and not addressing the hole are the LT4's only receiving partial can assistance?
4. Has this been discussed with other can companies, Elite?
The 'hole' you speak of is the source of crankcase ventilation on the LT4. If that tube is not blocked, any catch can installed is mostly useless on the LT4. The RX Products kit indeed addressed this. I have not seen the kits from Elite and CoSpeed but would assume their LT4 kits will as well as they would be useless without doing so.
08-17-2015, 11:02 AM
#159
Drifting
Member Since: Feb 2015
Location: Syracuse-Central Square New York Winer of the all Corvette race WGI 8/23!
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The 'hole' you speak of is the source of crankcase ventilation on the LT4. If that tube is not blocked, any catch can installed is mostly useless on the LT4. The RX Products kit indeed addressed this. I have not seen the kits from Elite and CoSpeed but would assume their LT4 kits will as well as they would be useless without doing so.
May be important issues at 6,000 rpm!
08-17-2015, 11:38 AM
#160
Melting Slicks
Interesting and what I thought. You say the RX can addresses this issue can you explain how it does? Do you have to remove the supercharger to plug it up? Would that cause to much crank case pressure and lead to blown seals and leaks.
May be important issues at 6,000 rpm!
May be important issues at 6,000 rpm!
below is one from a Magnasun SC at 14k miles as an example:
So you never want oil entering with these vapors. That is where the New Elite and CoSpeed systems reconfigure all of this to eliminate the causes, provide proper cross-flow flushing and evacuation, and trap not only the oil mist but also the other contaminates you do not want being ingested in the intake air charge.