LS6 PCV mod w/ breathers ......question.
12-11-2010, 07:57 PM
#1
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LS6 PCV mod w/ breathers ......question. Im looking at getting valve covers without the throttle body to passenger valve cover line. Any reason I couldnt do this with dual breathers and the LS6 PCV mod?
12-11-2010, 10:54 PM
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In the conversion section there are a lot of guys running carbs with the LS6 valley. You could search around there or the site in general and find some examples of the set-up you are talking about.
12-12-2010, 03:38 PM
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TTT...Im not looking at using carbs....I only want to know if I will have issues using dual breathers with the LS6 PCV mod on an LS1 without the use of the fresh air line from the throttle body. I would say there should be no problem but not ever having done this before Id like to get info from the experts 
12-12-2010, 06:38 PM
#4
TTT...Im not looking at using carbs....I only want to know if I will have issues using dual breathers with the LS6 PCV mod on an LS1 without the use of the fresh air line from the throttle body. I would say there should be no problem but not ever having done this before Id like to get info from the experts
12-12-2010, 08:16 PM
#6
I run 3 Breathers..
Drivers Head Rear(K&N from Any Auto Parts Store)
Passenger Head Front(oil Fill breather from many of the site vendors on the right)
and LS6 Valley Cover tube(smaller breather from any Auto parts store...)
no tubes go back into my intake from my engine
Drivers Head Rear(K&N from Any Auto Parts Store)
Passenger Head Front(oil Fill breather from many of the site vendors on the right)
and LS6 Valley Cover tube(smaller breather from any Auto parts store...)
no tubes go back into my intake from my engine
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12-12-2010, 09:49 PM
#8
yeah, it is. The pass side hose delivers fresh, filtered air to the engine, while the pcv removes not fresh crankcase fumes to the intake to burn.
You could easily run the pass side to a breather, it would do the same thing. I'm running the ls6 setup and have both the original pass air in, and have the old pcv hole welded up and running another air in at that location as well.
I've noticed on teardown of a couple 5.3's the air in side has far cleaner rockers/valve springs/pushrods than the pcv side, so I'm hoping this will help, but I won't be able to see for a LONG time lol.
You could easily run the pass side to a breather, it would do the same thing. I'm running the ls6 setup and have both the original pass air in, and have the old pcv hole welded up and running another air in at that location as well.
I've noticed on teardown of a couple 5.3's the air in side has far cleaner rockers/valve springs/pushrods than the pcv side, so I'm hoping this will help, but I won't be able to see for a LONG time lol.
12-13-2010, 02:23 AM
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He wasn't suggesting you use a carb. The breather set up is common with carded LS1 as they dont have a throttle body to attach the fresh air hose to. Not sure why you would want dual breathers, one would be fine. As a part of the LS6 conversion you will plug both valve covers PCV openings.
Also, the line on the front of the passenger valve cover is fresh air IN to the head and the two rear exits on a traditional LS1 or the valley on LS6 goes to the intake neck and THAT is vacuum, pulling the air into the intake behind the throttle body at low rpms keeping the crankcase evacuated.
12-13-2010, 05:23 AM
#10
To the OP,
This topic is beat to death all over the site. Should be able to find what is needed through a search.
The information that I'd like to find is a tear down difference between a properly set up PCV system which uses vacuum to pull fresh air into one side of the engine & out the other side, compared to just a breather set up that does not use the intake vacuum to pull fresh air. Long term, would expect the breather only set up to have more corrosion due to less movement of contaminants through the engine. Yah, the engine seals do just fine because the breathers allow pressure to escape, but, without the higher volume of fresh air being moved through the engine, corrosion is more of a factor, long term (this would not be the case in seasonal engines that are torn down seasonally. I am talking long term street use). Also, am not suggesting that the breathers don't pull any fresh air because there is a slight vacuum through normal leakage. It's just no where near the volume pulled by connecting the plumbing to the intake.
Then, there's the group w/ tuning software that can modify the tune for the unmeasured air entering a breather set up that is connected to the intake. On this set up, there is the larger volume of fresh air being pulled into the engine through the breathers that is not measured by the MAF. Speed density set ups can also use this system. W/ an LS6 valley nipple, IMO, this is the best "fresh air" solution because less restricted air is pulled through each head & out the valley; same as stock, but, w/ less restriction.
This topic is beat to death all over the site. Should be able to find what is needed through a search.
The information that I'd like to find is a tear down difference between a properly set up PCV system which uses vacuum to pull fresh air into one side of the engine & out the other side, compared to just a breather set up that does not use the intake vacuum to pull fresh air. Long term, would expect the breather only set up to have more corrosion due to less movement of contaminants through the engine. Yah, the engine seals do just fine because the breathers allow pressure to escape, but, without the higher volume of fresh air being moved through the engine, corrosion is more of a factor, long term (this would not be the case in seasonal engines that are torn down seasonally. I am talking long term street use). Also, am not suggesting that the breathers don't pull any fresh air because there is a slight vacuum through normal leakage. It's just no where near the volume pulled by connecting the plumbing to the intake.
Then, there's the group w/ tuning software that can modify the tune for the unmeasured air entering a breather set up that is connected to the intake. On this set up, there is the larger volume of fresh air being pulled into the engine through the breathers that is not measured by the MAF. Speed density set ups can also use this system. W/ an LS6 valley nipple, IMO, this is the best "fresh air" solution because less restricted air is pulled through each head & out the valley; same as stock, but, w/ less restriction.
12-13-2010, 09:44 AM
#12
What i don't like about the LS6 breather is the fact its right over the cam area. Its drawing all the moisture right past the cam and lifters constantly.
The Ls1 system is much better IMO but needs some tweaking. I'm sure the engineers at GM put quite a bit of thought into it but I think it should be a cross flow system. I think the proper place for the pcv is in the oil cap IF it was baffled. With the fresh air coming in on the left rear valve cover. I may try this soon, I need to make the oil cap functional 1st.
The Ls1 system is much better IMO but needs some tweaking. I'm sure the engineers at GM put quite a bit of thought into it but I think it should be a cross flow system. I think the proper place for the pcv is in the oil cap IF it was baffled. With the fresh air coming in on the left rear valve cover. I may try this soon, I need to make the oil cap functional 1st.
12-13-2010, 05:21 PM
#13
What i don't like about the LS6 breather is the fact its right over the cam area. Its drawing all the moisture right past the cam and lifters constantly.
The Ls1 system is much better IMO but needs some tweaking. I'm sure the engineers at GM put quite a bit of thought into it but I think it should be a cross flow system. I think the proper place for the pcv is in the oil cap IF it was baffled. With the fresh air coming in on the left rear valve cover. I may try this soon, I need to make the oil cap functional 1st.
The Ls1 system is much better IMO but needs some tweaking. I'm sure the engineers at GM put quite a bit of thought into it but I think it should be a cross flow system. I think the proper place for the pcv is in the oil cap IF it was baffled. With the fresh air coming in on the left rear valve cover. I may try this soon, I need to make the oil cap functional 1st.
You do realize that the air traveling through the block travels through the cam section regardless, right? Apparently, you do not. Whether the air goes from one head to another on its' way out or from a head through the valley cover, it passes through the area of the cam. Further, the main objective of the PCV is to relieve pressure & to vent acidic vapor from the block.
12-13-2010, 08:15 PM
#14
You do realize that the air traveling through the block travels through the cam section regardless, right? Apparently, you do not. Whether the air goes from one head to another on its' way out or from a head through the valley cover, it passes through the area of the cam. Further, the main objective of the PCV is to relieve pressure & to vent acidic vapor from the block.
12-13-2010, 08:42 PM
#15
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But i would have to agree that it seems like it would be better to have the air flow from one corner of the engine to the other.
12-14-2010, 05:02 AM
#16
Makes no difference either way. While parked in the garage, I run a water hose in through the valley cover just to make sure that plenty of moisture wrecks my cam... & crank for that matter. 
I shoulda known better than to waist more time in a PCV thread.
I shoulda known better than to waist more time in a PCV thread. 