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Discussion Starter · #1 ·
Hello,

Wondering if anyone has a good reason why I shouldn't do the following for

"OFF ROAD USE"

-Gut pvc value,
-connect to oil separator/collection tank
-vent to air

Thoughts?
 

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venting the PCV system into the atmosphere should be no problem, but if you have any sort of emission test and they spot it, it will fail. Also, the point where the system "vents" will get very oily so make sure it is not near any rubber parts.
 

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Discussion Starter · #7 ·
venting the PCV system into the atmosphere should be no problem, but if you have any sort of emission test and they spot it, it will fail. Also, the point where the system "vents" will get very oily so make sure it is not near any rubber parts.
I'm going to hook an oil catchcan in line, and put a filter on the vent end.

Sounds like an easy upgrade to me & no more oil in the intake tract.
 

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You were wondering if anyone had a good reason for not doing it...I'd say that is a perfectly viable response.

Typically when I think of modifying something, I try to think of a good reason why I should do it, not a good reason not to. What will the net benefit be? Do the benefits outweigh any potential issues?

The T7 motors tend to be a bit more sensitive when it comes to the PCV system. I personally wouldn't stray from the latest/greatest OEM PCV update. There is a reason why it has been updated to what it is today.
 

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Discussion Starter · #11 ·
Actually, when I am looking at the PVC system I think about what it is designed to do, and the constraints the factory designers had to operate under.

I don't necessarily think "hmm someone smart than me made this, I should respect it"
I'm not opposed to RTFM, but I have met plenty of clever ideas that didn't make common sense.

Obviously you can't dump exhaust fumes and oil into the environment (constraint)

But you want to most effectively dissipate pressure (goal)


Now, the factory fellas had to take 6 cracks at this to get it right, that concerns me.

I know what I am proposing will vent the pressure COMPLETELY and keep oil out of the intake.
 

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Discussion Starter · #12 ·
Under normal operation the PCV valve allows crankcase air to be drawn into the intake manifold when you have vacuum in the manifold. Once you make boost pressure, the PCV valve closes and the only ventilation the crankcase gets is thru the small hose that was running to the turbo inlet. By eliminating the PCV valve you can get twice the crankcase ventilation while under boost.
 

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Under normal operation the PCV valve allows crankcase air to be drawn into the intake manifold when you have vacuum in the manifold. Once you make boost pressure, the PCV valve closes and the only ventilation the crankcase gets is thru the small hose that was running to the turbo inlet. By eliminating the PCV valve you can get twice the crankcase ventilation while under boost.
Without the PCV check valve you will be pressurizing the valve cover/crankcase.

Why modify a proven system on a sludge prone car? Tell your Honda instincts to get out of your head.
 

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Under normal operation the PCV valve allows crankcase air to be drawn into the intake manifold when you have vacuum in the manifold. Once you make boost pressure, the PCV valve closes and the only ventilation the crankcase gets is thru the small hose that was running to the turbo inlet. By eliminating the PCV valve you can get twice the crankcase ventilation while under boost.
I think you are operating under the assumption that there is excess crankcase pressure when you are under boost. I highly doubt this is the case, unless you have some issues with your rings.
 

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Discussion Starter · #15 ·
I think you are operating under the assumption that there is excess crankcase pressure when you are under boost. I highly doubt this is the case, unless you have some issues with your rings.
I'm operating on two ideas:
1. Under boost pcv is closed
2. under boost there is more blowby (in proportion to amt of boost)
 

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Actually, when I am looking at the PVC system I think about what it is designed to do, and the constraints the factory designers had to operate under.

I don't necessarily think "hmm someone smart than me made this, I should respect it"
I'm not opposed to RTFM, but I have met plenty of clever ideas that didn't make common sense.

Obviously you can't dump exhaust fumes and oil into the environment (constraint)

But you want to most effectively dissipate pressure (goal)

Now, the factory fellas had to take 6 cracks at this to get it right, that concerns me.

I know what I am proposing will vent the pressure COMPLETELY and keep oil out of the intake.
Under normal operation the PCV valve allows crankcase air to be drawn into the intake manifold when you have vacuum in the manifold. Once you make boost pressure, the PCV valve closes and the only ventilation the crankcase gets is thru the small hose that was running to the turbo inlet. By eliminating the PCV valve you can get twice the crankcase ventilation while under boost.
WOOOOOOW. Step away from the PCV system, you have no idea what you're talking about. :lol:
 

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Yup, it goes to the intake. Under boost the intake literally sucks the crankcase fumes and pressure out. The crankcase is certainly not closed under boost :lol:
 

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I think you are operating under the assumption that there is excess crankcase pressure when you are under boost. I highly doubt this is the case, unless you have some issues with your rings.
Issues with rings such as low friction pistons? This is where the whole sludge and pvc problems originate.

The 9000 b234 which is nearly identical has a simple pcv system and has none of the same issues as the 9-5 does because it did not have these low friction pistons which actually do NOT seal as well as the b234 pistons (hence the low friction).

I am intrigued by this conversation, and I'm the first to admit I don't understand completely the pcv system on the 9-5. I put update 6 on mine, and still have oil leak that I have read is due to pcv issues.

I'll tell you one thing, I dont agree with "because somebody smarter than you..." when this pcv problem took 6 iterations to fix, and wasn't really fixed till 2003 model years.

Lets dicuss..... I've got alot to learn.
 

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The other function of the PCV system routed to the inlet is that it always (almost always) maintains the crankcase under vacuum, which helps the front and rear main crank seals ... well.... seal. If there is vacuum in the case, oil that would weep past the seals gets slurped back inside.

For those of you not paying attention, the acronym PCV means exactly that, if you vent it to atmostphere it's not PCV - it's what they had prior to the 1970's, when you just have a little breather filter.


Drew
 
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