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Quick question. I saw a stock ’04 the other day and the PCV system looked different. The line came out of the valley cover and went straight into the intake manifold with no valve inline. Is this how the ’02 ls6 cars were setup? I seem to remember seeing a valve on those.
So where is the valve? Is it integrated into the valley cover baffle?
I installed and ls6 valley cover on mine but I never checked to see if there was some type of integrated valve in the baffle.
I know this is better suited for the tech section, but I just feel I will get better answers here.
Sounds like they eliminated the valve in the line. The little spring loaded POS valve only controlled pressure one direction, although when it gets weak, boost pressure can overcome it. Maybe GM figured it was not needed anymore as long as the oil/vapor will blow back into the intake. As far as I am concerned its not even necessary.
I agree I have seen motors with the heads off that use alky/water injection, its amazing how clean everything is.
Are you saying you put in a PCV valve and a check valve or just a check valve.
My understanding is that a PCV valve is more of a vacuum regulator (it flows less as vacuum increases and more as vacuum drops). I want this behavior because I don’t want a bunch of unmetered air at idle/decel. This is only a concern when you run breathers, since the stock setup takes in metered air from just in front of the throttle body.
Shinobi,
I agree that it is not necessary, but I’m sick of the smell and want to start daily driving my car more.
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Originally Posted by QuickSilver2002
Doug,
Are you saying you put in a PCV valve and a check valve or just a check valve.
My understanding is that a PCV valve is more of a vacuum regulator (it flows less as vacuum increases and more as vacuum drops). I want this behavior because I don’t want a bunch of unmetered air at idle/decel. This is only a concern when you run breathers, since the stock setup takes in metered air from just in front of the throttle body.
Shinobi,
I agree that it is not necessary, but I’m sick of the smell and want to start daily driving my car more.
If you take a stock pcv valve and blow threw it, it will alow you to blow towards the intake (allowing vaccum) but not away from the intake (restricting boost from going into the crank case) so it sort of acts like a check valve. I know there are differences in pcv valves from year to year, or at least different part numbers, but they all seam to function the same. This is a good question for Phil (Roadrebel) since he has so much GM insight.
Last edited by DOUG @ ECS; Feb 3, 2005 at 09:50 AM.
Shinobi,
I agree that it is not necessary, but I’m sick of the smell and want to start daily driving my car more.
I know dude..but did you see the pics of Noob's motor when he had the heads off...that is the same reason I removed that POS PCV.
Originally Posted by DOUG @ ECS
If you take a stock pcv valve and blow threw it, it will alow you to blow towards the intake (allowing vaccum) but not away from the intake (restricting boost from going into the crank case) so it sort of acts like a check valve. I know there are differences in pcv valves from year to year, or at least different part numbers, but they all seam to function the same. This is a good question for Phil (Roadrunner) since he has so much GM insight.
This is precisely what I was referring too. I took one off a newer car once (newer than mine) and was able to blow back through it, towards the valley..back into the crankcase. Whereas, mine was older but still functioned as a check valve. There was a time when I even had a one way check vavle in place. I just ditched it..but as Quick mentioned it can kind of smell from time to time. I am wondering if I should have just ran a line from the valley with an air filter on that and routed it towards the bottom of the car, and then put back on my oil filler cap and see what happens. Oh and I think Phil goes by RoadRebel..unless of course Roadrunner is just your name for him.
Last edited by Shinobi'sZ; Feb 2, 2005 at 08:34 PM.
Noob,
How far are you willing to go to vac the crankcase? HotRod magazine says you can get 25 extra ponies but look how big this this is.
Wow, very interesting. Those things are $300 to $500 though and only draw 10" of vacuum. I think an electric pump operated by a boost controlled switch is the best avenue... whoever does something like that must be a really smart person.
Wow, very interesting. Those things are $300 to $500 though and only draw 10" of vacuum. I think an electric pump operated by a boost controlled switch is the best avenue... whoever does something like that must be a really smart person.
Mine was $25 out of a Caddy from the bone yard. I figured that GM would build a good unit because of the liability issues associated with brake system failure. But that unit looks like a good alternative. Edit: I found this on a suppliers website "The high-quality pump only comes on when you need it: an inline pressure switch turns the pump on at 18-inches of vacuum and shuts it off at 22-inches, ensuring that your brake booster always has a proper vacuum source." How can you deactivate the internal pressure switch? Hmm
One question though. Would you cap off the fresh air port when you install it? I suppose you should. Otherwise you'll never achieve actual static vacuum. Personally I believe that the fresh air port is needed to allow a free flow of air thru the crankcase to keep things clean and not stress the seals. I guess I'm more concerned about positive pressure than negative pressure(oxymoron, but you know what I mean).