Catch Can and PCV Routing
#1
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I was looking at this post:
https://ls1tech.com/forums/11059703-post70.html
And I see that the rear passenger side valve cover port is plugged and the PCV valve is before the catch can. Looking at the LS6 valley cover diagram there is no passenger rear port to block and it has the PCV valve after the catch can.
Does it matter if the PCV value is before or after the catch can?
And why on the LS1 valley cover setup should you block that back port? Why wouldn't you just leave it in with the rest of the system?
https://ls1tech.com/forums/11059703-post70.html
And I see that the rear passenger side valve cover port is plugged and the PCV valve is before the catch can. Looking at the LS6 valley cover diagram there is no passenger rear port to block and it has the PCV valve after the catch can.
Does it matter if the PCV value is before or after the catch can?
And why on the LS1 valley cover setup should you block that back port? Why wouldn't you just leave it in with the rest of the system?
#3
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You want a "loop" of bad/good air. Bad gasses evacuated from the back of one or both valvecovers, through the catch can via the nipple behind the throttle body. Good air from the forward nipple on the TB into the front of the valvecover. Everything else has to be plugged or there is a leak in the loop and it won't do it's job. The PCV valve is a one way check valve to keep this loop unidirectional (positive crankcase ventilation). I guess where it is wouldn't matter as long as it's between the rear TB and the rear valvecover and facing the right way. Seems it wouldn't get boogered up with oil as much after the catch can.
Upgrade your lines and fittings with fuel line, sturdy fittings and hose clamps so your not chasing leaks with the stock crappy stuff. Do it once right and be done with it. I was confused by those diagrams as well. I put my valve right off the catchcan. It catches a few tablespoons after a thousand or so miles of spirited driving.
A few pictures here: https://ls1tech.com/forums/generatio...ctly-pics.html
Upgrade your lines and fittings with fuel line, sturdy fittings and hose clamps so your not chasing leaks with the stock crappy stuff. Do it once right and be done with it. I was confused by those diagrams as well. I put my valve right off the catchcan. It catches a few tablespoons after a thousand or so miles of spirited driving.
A few pictures here: https://ls1tech.com/forums/generatio...ctly-pics.html
Last edited by Steve Gunn; 11-13-2010 at 07:37 PM.
#4
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I was looking at this post:
https://ls1tech.com/forums/11059703-post70.html
And I see that the rear passenger side valve cover port is plugged and the PCV valve is before the catch can. Looking at the LS6 valley cover diagram there is no passenger rear port to block and it has the PCV valve after the catch can.
Does it matter if the PCV value is before or after the catch can?
And why on the LS1 valley cover setup should you block that back port? Why wouldn't you just leave it in with the rest of the system?
https://ls1tech.com/forums/11059703-post70.html
And I see that the rear passenger side valve cover port is plugged and the PCV valve is before the catch can. Looking at the LS6 valley cover diagram there is no passenger rear port to block and it has the PCV valve after the catch can.
Does it matter if the PCV value is before or after the catch can?
And why on the LS1 valley cover setup should you block that back port? Why wouldn't you just leave it in with the rest of the system?
I recommend plugging this port because of it's proximity to the clean air intake port. One of the objectives of the PCV system is to remove contaminated crankcase byproducts. Removing this path from the PCV system forces crankcase byproducts out the valley cover.
You can place the PCV valve on either side of the catch can.
Another thread with lots of good discussion and diagrams: https://ls1tech.com/forums/generatio...outing-ok.html
Last edited by 405HP_Z06; 11-16-2010 at 02:22 PM.