PCV ROUTING with catchcan
Thread Starter
Launching!
Joined: Feb 2006
Posts: 270
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PCV ROUTING with catchcan I couldn't get a response over at CF or ZO6, so I'll ask here as well. I've got a LS2 TB, which only has one outlet for the PCV line, and none for the vent from the passenger side valve cover. (LS6, 'natch) I just installed a Vararam intake, which has a pre-MAF inlet for the AIR system.(which I've eliminated) I'm going to install a catch-can off the valley cover/PCV line, and wondered if it was a good idea to route the outlet of this line to the inlet on the Vararam? I would then use the out/in/whatever vent from the pass. side valve cover line, and run it to the TB out/inlet. This would keep only metered air in the motor, and work out the same way in the final analysis, right? Thanks....
Originally Posted by exSSer
I couldn't get a response over at CF or ZO6, so I'll ask here as well. I've got a LS2 TB, which only has one outlet for the PCV line, and none for the vent from the passenger side valve cover. (LS6, 'natch) I just installed a Vararam intake, which has a pre-MAF inlet for the AIR system.(which I've eliminated) I'm going to install a catch-can off the valley cover/PCV line, and wondered if it was a good idea to route the outlet of this line to the inlet on the Vararam? I would then use the out/in/whatever vent from the pass. side valve cover line, and run it to the TB out/inlet. This would keep only metered air in the motor, and work out the same way in the final analysis, right? Thanks....
The problem with directing it to the "AIR" inlet is that even though you have a catch can, you will still have oily fumes...and they will foul your MAF sensor wires.
Hammer
The seperated air line leaving the catch can needs to be plugged into the manifold anywhere BEHIND the throttle body blade.
The crankcase air inlet (fresh air tube), usually has a line from the front of the passenger side valve cover to the throttle body, and it pulls from in front of the blade (higher pressure than behind the blade).
If your lines aren't in this configuration, you won't have any kind of motive force to draw fresh air into the crankcase. The pressure differential on either side of the TB blade is what causes it. The LS2 manifold should have a port for the PCV behind the throttle body flange, this is where the line leaving your catch can should go. Leave the valve cover to throttle body line alone.
I hope this is comprehensible lol.
The crankcase air inlet (fresh air tube), usually has a line from the front of the passenger side valve cover to the throttle body, and it pulls from in front of the blade (higher pressure than behind the blade).
If your lines aren't in this configuration, you won't have any kind of motive force to draw fresh air into the crankcase. The pressure differential on either side of the TB blade is what causes it. The LS2 manifold should have a port for the PCV behind the throttle body flange, this is where the line leaving your catch can should go. Leave the valve cover to throttle body line alone.
I hope this is comprehensible lol.
Thread Starter
Launching!
Joined: Feb 2006
Posts: 270
Likes: 0
Originally Posted by TheBlurLS1
The seperated air line leaving the catch can needs to be plugged into the manifold anywhere BEHIND the throttle body blade.
The crankcase air inlet (fresh air tube), usually has a line from the front of the passenger side valve cover to the throttle body, and it pulls from in front of the blade (higher pressure than behind the blade).
If your lines aren't in this configuration, you won't have any kind of motive force to draw fresh air into the crankcase. The pressure differential on either side of the TB blade is what causes it. The LS2 manifold should have a port for the PCV behind the throttle body flange, this is where the line leaving your catch can should go. Leave the valve cover to throttle body line alone.
I hope this is comprehensible lol.
The crankcase air inlet (fresh air tube), usually has a line from the front of the passenger side valve cover to the throttle body, and it pulls from in front of the blade (higher pressure than behind the blade).
If your lines aren't in this configuration, you won't have any kind of motive force to draw fresh air into the crankcase. The pressure differential on either side of the TB blade is what causes it. The LS2 manifold should have a port for the PCV behind the throttle body flange, this is where the line leaving your catch can should go. Leave the valve cover to throttle body line alone.
I hope this is comprehensible lol.
These have been helpful, but.... I have a FAST manifold with the LS2 TB, and there's no provision for an add'l PCV line on the manifold. It makes sense what Hammer says, not to foul the MAF. I can always use the TB port, as originally intended, for the outlet of the catch-can, but I still don't know what to do with the vent from the valve cover, since it's supposed to use "metered" air. Maybe I have to tap a hole, post-MAF, just for this line, but it'll have to seal well, I'd think.
