Please not another crankcase ventilation thread.
10-26-2015, 12:30 PM
#81
Senior Member
Join Date: Feb 2009
Location: Philadelphia
Posts: 916
Total Cats: 70
I'll chime in here since I've had 2 blackstone analysis done with different results
Can was plumbed to both sides of the valve cover (no PCV) and had a breather on top. The resulting fuel content of the oil was 1.5%, as well as the flashpoints and general life of the oil being low.
Then I changed to a setup with PCV that pulls from PCV side, through a sealed can, back into intake manifold, and have a breather on the exhaust side port of the valve cover. Fuel content of the oil was down to under .5% and overall oil health was improved
Can was plumbed to both sides of the valve cover (no PCV) and had a breather on top. The resulting fuel content of the oil was 1.5%, as well as the flashpoints and general life of the oil being low.
Then I changed to a setup with PCV that pulls from PCV side, through a sealed can, back into intake manifold, and have a breather on the exhaust side port of the valve cover. Fuel content of the oil was down to under .5% and overall oil health was improved
Reply
0
0
10-26-2015, 12:33 PM
#82
SADFab Destructive Testing Engineer
iTrader: (5)
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,642
Total Cats: 1,866
I'll chime in here since I've had 2 blackstone analysis done with different results
Can was plumbed to both sides of the valve cover (no PCV) and had a breather on top. The resulting fuel content of the oil was 1.5%, as well as the flashpoints and general life of the oil being low.
Then I changed to a setup with PCV that pulls from PCV side, through a sealed can, back into intake manifold, and have a breather on the exhaust side port of the valve cover. Fuel content of the oil was down to
Can was plumbed to both sides of the valve cover (no PCV) and had a breather on top. The resulting fuel content of the oil was 1.5%, as well as the flashpoints and general life of the oil being low.
Then I changed to a setup with PCV that pulls from PCV side, through a sealed can, back into intake manifold, and have a breather on the exhaust side port of the valve cover. Fuel content of the oil was down to
Reply
0
0
10-26-2015, 01:08 PM
#87
Moderator
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 20,657
Total Cats: 3,011
What roughly was the lifespan of each oil being sampled? Is yours a street, track, or mixed application? I like that you have some data here to contemplate.
I don't street my car much except for testing. It gets maybe 400-500 miles between changes because it needs fresh oil for the abuse of the track.
I don't street my car much except for testing. It gets maybe 400-500 miles between changes because it needs fresh oil for the abuse of the track.
Reply
0
0
10-26-2015, 01:41 PM
#88
Senior Member
Join Date: Feb 2009
Location: Philadelphia
Posts: 916
Total Cats: 70
What roughly was the lifespan of each oil being sampled? Is yours a street, track, or mixed application? I like that you have some data here to contemplate.
I don't street my car much except for testing. It gets maybe 400-500 miles between changes because it needs fresh oil for the abuse of the track.
I don't street my car much except for testing. It gets maybe 400-500 miles between changes because it needs fresh oil for the abuse of the track.
2000 miles on setup 2
Setup 1 consisted of street driving, street tuning, dyno tuning. Driving was to work casually commuting, sometimes going out for spirited drives, no track time. I'd say the car got worked pretty hard when we were on it, but otherwise, I drive like a sane human being. When I take it out for a fun drive however, I generally wait for the local windy roads to clear out by midnight or 1am and go out at a fun pace.
Setup 2 consisted of street driving, no tuning, but lots of racing in "mexico", and a bunch of spirited drives. No track time here either as I was still chasing some issues with my tune (phantom knock). I'd say the car still got worked pretty hard when we were on it.
Nothing really compares to track driving though with sustained revs, boost, and general abuse. I will continue to do Blackstones in the name of science, and for the sake of catching things like bearing wear early before they destroy other things.
edit: I have not opened my intake manifold to take a look inside, but when I pulled the spark plugs, they looked normal.
Last edited by Mazdaspeeder; 10-26-2015 at 01:53 PM.
Reply
0
0
10-26-2015, 01:54 PM
#89
Junior Member
Join Date: May 2008
Location: Grants Pass, OR.
Posts: 488
Total Cats: 17
I thought that the discussion was about this, you just posted a paragraph with the above statement in it, so now you agree that an air source is needed to be efficient.
Last edited by jmann; 10-26-2015 at 02:33 PM.
Reply
0
0
10-26-2015, 02:56 PM
#91
Wiki wiki wiki wiki.
Large diesel engines use a draft tube and breather to this day.
So, the PCV valve is an emissions device unless you are fording a river with a tank. And it is implemented because it is federally mandated for the control of hydrocarbon emissions. This is what I stated previously.
Anyone removing an oil filler cap from a typical running engine, even one equipped with a PCV valve, could certainly attest to the fact that blow-by exists in far greater volumes than the PCV valve is allowing the engine to ingest. This blow-by is constantly increasing in volume as the engine is running (just like exhaust because much of it is just exhaust that has made it past the rings) and can be piped to an oil separator catch tank and vented to atmosphere if one is unconcerned with emissions.
I am simply stating, again, that the consumption of crankcase vapors and the introduction of outside air to an engine crankcase while it is running is not a performance benefit but an ecological one. And I choose not to contaminate my combustion chambers unnecessarily with oil and other foul byproducts of the combustion process. I have seen the nasty trail within an intake manifold around the inlet for the PCV hose and do not wish to add those elements to my freshly rebuilt engine.
Large diesel engines use a draft tube and breather to this day.
So, the PCV valve is an emissions device unless you are fording a river with a tank. And it is implemented because it is federally mandated for the control of hydrocarbon emissions. This is what I stated previously.
Anyone removing an oil filler cap from a typical running engine, even one equipped with a PCV valve, could certainly attest to the fact that blow-by exists in far greater volumes than the PCV valve is allowing the engine to ingest. This blow-by is constantly increasing in volume as the engine is running (just like exhaust because much of it is just exhaust that has made it past the rings) and can be piped to an oil separator catch tank and vented to atmosphere if one is unconcerned with emissions.
I am simply stating, again, that the consumption of crankcase vapors and the introduction of outside air to an engine crankcase while it is running is not a performance benefit but an ecological one. And I choose not to contaminate my combustion chambers unnecessarily with oil and other foul byproducts of the combustion process. I have seen the nasty trail within an intake manifold around the inlet for the PCV hose and do not wish to add those elements to my freshly rebuilt engine.
But yes it's an emissions device. And it can help extend oil life in a street car.
I don't run PCV on my car for the same reason you don't run it. I keep my oil changed.
Reply
0
0
10-26-2015, 03:12 PM
#92
Senior Member
Join Date: Feb 2009
Location: Philadelphia
Posts: 916
Total Cats: 70
I wonder how much the vapors you eliminate by eliminating the PCV actually hurt the octane as someone said. And how intense of a blow-by you would have to have for this to make a real difference. Wouldn't an ECU be reading the octane at all times and be compensating for any changes?
Reply
0
0
10-26-2015, 03:23 PM
#93
I wonder how much the vapors you eliminate by eliminating the PCV actually hurt the octane as someone said. And how intense of a blow-by you would have to have for this to make a real difference. Wouldn't an ECU be reading the octane at all times and be compensating for any changes?
Also consider that when you intake manifold is coated with oil from a PCV system, and then you go wide open, the air speed inside the manifold rises to its highest levels. That's when it's going to suck all the oil from the intake into the engine- at full power. Not ideal from a reliability or octane standpoint. But great for emissions.
Reply
0
0
10-26-2015, 03:44 PM
#94
Senior Member
Join Date: Feb 2009
Location: Philadelphia
Posts: 916
Total Cats: 70
My car doesn't have an octane sensor inside the intake manifold, downstream of the PCV system, for every cylinder. So it doesn't read the octane. Or model it. Not aware of any car that does this to compensate for PCV.
Also consider that when you intake manifold is coated with oil from a PCV system, and then you go wide open, the air speed inside the manifold rises to its highest levels. That's when it's going to suck all the oil from the intake into the engine- at full power. Not ideal from a reliability or octane standpoint. But great for emissions.
Also consider that when you intake manifold is coated with oil from a PCV system, and then you go wide open, the air speed inside the manifold rises to its highest levels. That's when it's going to suck all the oil from the intake into the engine- at full power. Not ideal from a reliability or octane standpoint. But great for emissions.
As far as IM cleanliness, I have to say that when we did my Skunk 2 TB, we took off the top of the plenum, and I remember being very happy about the cleanliness of my IM runners. That was after having the setup for about 1000-1500 miles, again, no track, but hard pulls here and there, and I love the sunday night drags (no homo). Perhaps my ring seal is just good and I'm not getting a lot of blow-by. Perhaps my catch-can is doing a good job. I do have a section in there with some steel wool that helps catch the oil on the way in. It is not otherwise baffled inside.
This is the can I have:
https://i486.photobucket.com/albums/...ps71e28f98.jpg
Reply
0
0
10-26-2015, 04:30 PM
#95
Wiki wiki wiki wiki.
Large diesel engines use a draft tube and breather to this day.
So, the PCV valve is an emissions device unless you are fording a river with a tank. And it is implemented because it is federally mandated for the control of hydrocarbon emissions. This is what I stated previously.
Anyone removing an oil filler cap from a typical running engine, even one equipped with a PCV valve, could certainly attest to the fact that blow-by exists in far greater volumes than the PCV valve is allowing the engine to ingest. This blow-by is constantly increasing in volume as the engine is running (just like exhaust because much of it is just exhaust that has made it past the rings) and can be piped to an oil separator catch tank and vented to atmosphere if one is unconcerned with emissions.
I am simply stating, again, that the consumption of crankcase vapors and the introduction of outside air to an engine crankcase while it is running is not a performance benefit but an ecological one. And I choose not to contaminate my combustion chambers unnecessarily with oil and other foul byproducts of the combustion process. I have seen the nasty trail within an intake manifold around the inlet for the PCV hose and do not wish to add those elements to my freshly rebuilt engine.
Large diesel engines use a draft tube and breather to this day.
So, the PCV valve is an emissions device unless you are fording a river with a tank. And it is implemented because it is federally mandated for the control of hydrocarbon emissions. This is what I stated previously.
Anyone removing an oil filler cap from a typical running engine, even one equipped with a PCV valve, could certainly attest to the fact that blow-by exists in far greater volumes than the PCV valve is allowing the engine to ingest. This blow-by is constantly increasing in volume as the engine is running (just like exhaust because much of it is just exhaust that has made it past the rings) and can be piped to an oil separator catch tank and vented to atmosphere if one is unconcerned with emissions.
I am simply stating, again, that the consumption of crankcase vapors and the introduction of outside air to an engine crankcase while it is running is not a performance benefit but an ecological one. And I choose not to contaminate my combustion chambers unnecessarily with oil and other foul byproducts of the combustion process. I have seen the nasty trail within an intake manifold around the inlet for the PCV hose and do not wish to add those elements to my freshly rebuilt engine.
The PCV was invented for tanks to ford rivers, it just so happened to be about around the same time we got all environmentally friendly, so it were called an emissions device. Lots of cool **** discovered during WW2 makes our lives better to this day, pcv one of them. The fact that it's so simple and works so well is a feat of modern engineering, all from a slug of lead and two springs...
My argument is this, again, if the blowby is cleaned by blowby, why's it matter if there is a pcv for clearing a river? May as well just send the breather up on a pole, 30 feet up?
Answer, clean oil lasts longer, even if you are fording a river. It lasts exponentially longer, so much so that it's worth all the trouble.
We've now got the Blackstone results (that I mentioned earlier) in this thread showing that in under 2K miles a proper PCV setup kills it, oil lasts longer.
Reply
0
0
10-26-2015, 04:40 PM
#96
Senior Member
Join Date: Feb 2009
Location: Philadelphia
Posts: 916
Total Cats: 70
1700 miles on setup 1
2000 miles on setup 2
Setup 1 consisted of street driving, street tuning, dyno tuning. Driving was to work casually commuting, sometimes going out for spirited drives, no track time. I'd say the car got worked pretty hard when we were on it, but otherwise, I drive like a sane human being. When I take it out for a fun drive however, I generally wait for the local windy roads to clear out by midnight or 1am and go out at a fun pace.
Setup 2 consisted of street driving, no tuning, but lots of racing in "mexico", and a bunch of spirited drives. No track time here either as I was still chasing some issues with my tune (phantom knock). I'd say the car still got worked pretty hard when we were on it.
Nothing really compares to track driving though with sustained revs, boost, and general abuse. I will continue to do Blackstones in the name of science, and for the sake of catching things like bearing wear early before they destroy other things.
edit: I have not opened my intake manifold to take a look inside, but when I pulled the spark plugs, they looked normal.
2000 miles on setup 2
Setup 1 consisted of street driving, street tuning, dyno tuning. Driving was to work casually commuting, sometimes going out for spirited drives, no track time. I'd say the car got worked pretty hard when we were on it, but otherwise, I drive like a sane human being. When I take it out for a fun drive however, I generally wait for the local windy roads to clear out by midnight or 1am and go out at a fun pace.
Setup 2 consisted of street driving, no tuning, but lots of racing in "mexico", and a bunch of spirited drives. No track time here either as I was still chasing some issues with my tune (phantom knock). I'd say the car still got worked pretty hard when we were on it.
Nothing really compares to track driving though with sustained revs, boost, and general abuse. I will continue to do Blackstones in the name of science, and for the sake of catching things like bearing wear early before they destroy other things.
edit: I have not opened my intake manifold to take a look inside, but when I pulled the spark plugs, they looked normal.
Pardon my ignorance in regards to tuning, I had a professional tune my car, so some of the things I "understand" might be false. I played with tuner studio software and saw there is an AFR target table, as well as some required fuel. I thought that the MS constantly compared the target vs actual values and could compensate for things. I may be 200% off base here.
As far as IM cleanliness, I have to say that when we did my Skunk 2 TB, we took off the top of the plenum, and I remember being very happy about the cleanliness of my IM runners. That was after having the setup for about 1000-1500 miles, again, no track, but hard pulls here and there, and I love the sunday night drags (no homo). Perhaps my ring seal is just good and I'm not getting a lot of blow-by. Perhaps my catch-can is doing a good job. I do have a section in there with some steel wool that helps catch the oil on the way in. It is not otherwise baffled inside.
This is the can I have:
https://i486.photobucket.com/albums/...ps71e28f98.jpg
As far as IM cleanliness, I have to say that when we did my Skunk 2 TB, we took off the top of the plenum, and I remember being very happy about the cleanliness of my IM runners. That was after having the setup for about 1000-1500 miles, again, no track, but hard pulls here and there, and I love the sunday night drags (no homo). Perhaps my ring seal is just good and I'm not getting a lot of blow-by. Perhaps my catch-can is doing a good job. I do have a section in there with some steel wool that helps catch the oil on the way in. It is not otherwise baffled inside.
This is the can I have:
https://i486.photobucket.com/albums/...ps71e28f98.jpg
Reply
0
0
10-26-2015, 05:43 PM
#97
Elite Member
Join Date: Apr 2010
Location: Newcastle, Australia
Posts: 2,826
Total Cats: 67
Initially you get a bubble then the hose draws a little water and then the water goes up and down the hose a little. So yeah the gases move but they dont travel out of the engine, thats mostly the cams moving air in and out.
Dann
Reply
0
0
10-26-2015, 05:44 PM
#98
Moderator
iTrader: (12)
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 20,657
Total Cats: 3,011
The Blackstone results with a sample size of one and few controls of variables is science in your view? Interesting. Please tell us more about how things are proven. I am truly curious.
And please, again, do watch the name calling. I have stuck to the details of the topic and advise you to be courteous in your objections.
Reply
0
0
10-26-2015, 05:58 PM
#99
I'm sorry, I don't know how else to respond to your last post. Tanks don't need to be efficient, but according to Wikipedia they are the first ever use of the valves. Your argument of "PCV valve is for emissions except tank" makes absolutely no sense, as they could just as easily not have a PCV valve...
All of that is meaningless though, as the draft tube was and still is a thing. Instead of deleting the draft tube which is not an emissions device, they thought it beneficial to continue force feeding the crank fresh air. Coincidence?
If you are worried about oil ingestion, install a draft tube. I guarantee better oil life with airflow through the crank, and would gladly pay for Blackstone results to prove my claims. I still think a PCV valve would outperform a draft tube, by a wide margin...
I'm done, though, no mas from me. I believe I've made my point.
All of that is meaningless though, as the draft tube was and still is a thing. Instead of deleting the draft tube which is not an emissions device, they thought it beneficial to continue force feeding the crank fresh air. Coincidence?
If you are worried about oil ingestion, install a draft tube. I guarantee better oil life with airflow through the crank, and would gladly pay for Blackstone results to prove my claims. I still think a PCV valve would outperform a draft tube, by a wide margin...
I'm done, though, no mas from me. I believe I've made my point.
Reply
0
0
10-26-2015, 06:10 PM
#100
Senior Member
Join Date: Feb 2009
Location: Philadelphia
Posts: 916
Total Cats: 70
Well this got serious lol....The only "controls" I have over the test are when the oil is collected. In both instances, I drove to the same mechanic the same distance from my home. We waited the same amount of time (10 minutes) to drain the oil. Pull the plug, count to 3, then fill the jar.
I can't think of anything I changed on the vehicle that would have affected the fuel content of the oil at all, let alone that much, besides that catch-can. My mechanic was telling me for a while that if I cared about my oil, I should change the setup from the vented can I had. Seeing my Blackstone results confirmed that decision. I was dually happy when the latest results proved his argument.
I can't think of anything I changed on the vehicle that would have affected the fuel content of the oil at all, let alone that much, besides that catch-can. My mechanic was telling me for a while that if I cared about my oil, I should change the setup from the vented can I had. Seeing my Blackstone results confirmed that decision. I was dually happy when the latest results proved his argument.
Last edited by Mazdaspeeder; 10-26-2015 at 06:24 PM.
Reply
0
0
