LS1 to LS6 PVC conversion help
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On The Tree
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From: Tampa,Fl
LS1 to LS6 PVC conversion help Has any one used the LS6 valley cover number 12577927, and Gm part number 12594779 (hose) To do the LS1 to LS6 PVC conversion?
Part number 12577927 is supposed to be the 2004 LS6 cover with a built in PVC valve. And the hose numbered 12594779 is supposed to be a U shaped hose to connect the Valley cover to the T/B. Is this correct or is there more to this that I am missing. I already have part number 12577927, my car is a 2002 LS1 Vette.
Thanks
Part number 12577927 is supposed to be the 2004 LS6 cover with a built in PVC valve. And the hose numbered 12594779 is supposed to be a U shaped hose to connect the Valley cover to the T/B. Is this correct or is there more to this that I am missing. I already have part number 12577927, my car is a 2002 LS1 Vette.
Thanks
I do not know what the part numbers are but I have been using a LS6 valley cover and the LS6 PCV and hose for 60,000 + miles now. I also run a breather in the oil fill on the passenger side valve cover..these vavle covers do not have any of the hose connections like the stock ones do ... it works like a champ .. 
You also need 12556454 hose (RH valve cover to intake).
The 01-03 Z06 used valley cover 12568002 that used pcv hose 12573109 that contained the pcv valve and connected to both valve covers.
The 01-03 Z06 used valley cover 12568002 that used pcv hose 12573109 that contained the pcv valve and connected to both valve covers.
I swapped over to the LS6 valley cover to clean up some of those vacuum lines and you can just cut the hose off of your old pcv system and attatch it to the nipple of the LS6. I would highly recommend this over the valve cover breather, basically because the PCV (positive crankcase pressure) is used to redirect the blowby created by the pressure within the crankcase meaning a slight oilmist must be redirected into the motor (thus the oil in your intake manifold) to keep it from bursting. When using the valve cover breather you are leting that pressure vent into the atmosphere, but what is also vented? (oil mist). The LS6 allows that blowby to be delt with, in the crankcase itself, meaning no silly vacuum lines running from one valve cover to the other....in simple terms, the LS6 is a more direct means of crankcase ventalation.
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I swapped over to the LS6 valley cover to clean up some of those vacuum lines and you can just cut the hose off of your old pcv system and attatch it to the nipple of the LS6. I would highly recommend this over the valve cover breather, basically because the PCV (positive crankcase pressure) is used to redirect the blowby created by the pressure within the crankcase meaning a slight oilmist must be redirected into the motor (thus the oil in your intake manifold) to keep it from bursting. When using the valve cover breather you are leting that pressure vent into the atmosphere, but what is also vented? (oil mist). The LS6 allows that blowby to be delt with, in the crankcase itself, meaning no silly vacuum lines running from one valve cover to the other....in simple terms, the LS6 is a more direct means of crankcase ventalation.
your pcv at wot does not evacuate anything, theres no vacumn, thats when a breather changes from air in to pressure out. the biggest effect a breather has is its not metered at all by the maf so some pcm parameters may be scewed in stock form. nothing major imo but every car is different.
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I swapped over to the LS6 valley cover to clean up some of those vacuum lines and you can just cut the hose off of your old pcv system and attatch it to the nipple of the LS6. I would highly recommend this over the valve cover breather, basically because the PCV (positive crankcase pressure) is used to redirect the blowby created by the pressure within the crankcase meaning a slight oilmist must be redirected into the motor (thus the oil in your intake manifold) to keep it from bursting. When using the valve cover breather you are leting that pressure vent into the atmosphere, but what is also vented? (oil mist). The LS6 allows that blowby to be delt with, in the crankcase itself, meaning no silly vacuum lines running from one valve cover to the other....in simple terms, the LS6 is a more direct means of crankcase ventalation.
Thank-you for trying to assist. However, please note the proper set-up & operation of the PCV system prior to giving advice.
For all in this thread there is a thread titled "missconeptions about PCV..." that will be helpfull. The title isn't exactly as I have noted, but a search for those words should find the information.
I did this conversion, however, I did not use that hose. I used a catch can and went to the auto parts store and found a PCV to put inline. Some catchcans have a PCV included, however the way I did it is way cheaper. I bought my catch can from catchcans.com. Theirs does not have a built in PCV, but I can provide the part number for the one I have. Here is a picture
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I do not know what the part numbers are but I have been using a LS6 valley cover and the LS6 PCV and hose for 60,000 + miles now. I also run a breather in the oil fill on the passenger side valve cover..these vavle covers do not have any of the hose connections like the stock ones do ... it works like a champ ..
ur pcv setup is wrong, when u run the ls6 setup ur supposed run it to the intake only, if u put a breather then ur car is pulling vaccum from from 2 places, that causes for unmeasured air to go into ur car, u have to either block off the intake entrance and run a breather from the ls6 valley cover if u have a breather on the valve cover, or u need to take off valve cover breather, i know its confusing but thats what the real gurus will tell you, do some research, im not knocking ur setup, just trying to pass some knowledge that the gurus here told me
ur pcv setup is wrong, when u run the ls6 setup ur supposed run it to the intake only, if u put a breather then ur car is pulling vaccum from from 2 places, that causes for unmeasured air to go into ur car, u have to either block off the intake entrance and run a breather from the ls6 valley cover if u have a breather on the valve cover, or u need to take off valve cover breather, i know its confusing but thats what the real gurus will tell you, do some research, im not knocking ur setup, just trying to pass some knowledge that the gurus here told me
I make 452 rwhp the car is DD and has over 170,000 miles on it ...it sees the red line every day..it uses 1/2 quart of oil every 5,000 miles and has no oil in the intake manifold...been using this set up for close to 70,000 miles now so it seems to be working just fine..I subscribe to the if it aint broke dont fix it school of thought..thanks for your input.
He didn't say that your set-up wouldn't work. He said that it is technically incorrect. The way your PCV system is set up will tax the fuel trims.
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You can rest assured that it is tuned correctly and makes plenty of power and gets good fuel economy too (26.5 on hwy-20 around town) not to mention no oil consumption and no oil in the intake ...like I said if it is not broke dont fix it..
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On The Tree
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Thank for all the input from all, didn't want the post to cause war between folks getting back to me.
I received an e-mail from Gene at gm parts He told me that the 04' cover has an internal orifice built into the part and does away with the PVC valve. Just like voda1 said.
I am going to do the install soon. I will probably run a catch can also just as an added back up system. I plan on running a catch can with a removable cap so I can add steel wool to the inside just to help the oil/water vapor to change from a vapor to a liquid and settle down to the bottom.
Eventually I will get the same valve covers as themack56. Your engine looks great.
slt200mph, I know you know what you are doing, your posts all sound like they come from first hand experience. I only hope that after I finish all my mods that my car will have a similar HP out put, and reliability as yours.
Again, for every body Thanks
I received an e-mail from Gene at gm parts He told me that the 04' cover has an internal orifice built into the part and does away with the PVC valve. Just like voda1 said.
I am going to do the install soon. I will probably run a catch can also just as an added back up system. I plan on running a catch can with a removable cap so I can add steel wool to the inside just to help the oil/water vapor to change from a vapor to a liquid and settle down to the bottom.
Eventually I will get the same valve covers as themack56. Your engine looks great.
slt200mph, I know you know what you are doing, your posts all sound like they come from first hand experience. I only hope that after I finish all my mods that my car will have a similar HP out put, and reliability as yours.
Again, for every body Thanks
You are correct, 04 and up LS6 valley pans have a built in PCV. Early LS6 eliminates the valve cover vents too, other than the one on the front right, but do not have that feature. I didnt know that when I purchased my valley pan, so I got the early style and so had to run the external PCV. It was only $1.99 so no biggie.
Any new news on this new style valley cover twospeed? Was wondering if you are seeing less oil in the intake? I'm running the older style LS6 valley cover and PCV valve and a catch can and still getting oil in the intake. Looking for another option.