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Old 10-26-2024, 06:15 PM   #1
Ziegelsteinfaust
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Pcv valves

I am fixing my dad's Hot-Rod a 29 Model up as I have time. As all the problems are small, and don't effect it much as a matter of running.

So to clean it up as I go.

Can you run the pvc system in the back of the intake manifold where your just above the lifter valley?
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Old 10-27-2024, 10:36 AM   #2
Willshook
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Re: Pcv valves

Cool

I think you'd be OK using any intake manifold vacuum source, but I'm not clear on where you want to connect. Can you share a picture?
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Old 10-27-2024, 11:13 AM   #3
Ziegelsteinfaust
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Re: Pcv valves

I meant drilling a hole in the manifold, and putting the pvc valve there.
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Old 10-27-2024, 11:25 AM   #4
Willshook
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Re: Pcv valves

I'm hesitant to answer without understanding exactly where you're looking to drill...
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Old 10-27-2024, 12:26 PM   #5
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Re: Pcv valves

In the lifter valley I'd be concerned about drawing too much oil through the system, plus I don't know how you would seal it up unless you found the perfect grommet in compliance with the thickness of the manifold
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Old 10-29-2024, 05:46 PM   #6
Wrenchbender Ret
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Re: Pcv valves

You need to tell us what engine you are working with. You can't put the pcv valve any where in an intake manifold runner. If it pulls the vacuum from just part of manifold that runs to separate cylinder/s you will get a rough idle. It needs to be at the carb or close to it.

George
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Old 10-29-2024, 10:31 PM   #7
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Re: Pcv valves

Is there some reason not to do it the way the factory designed PCV? Draw air into one valve cover and pull it out via the other side?

Even if you find a way to put one in the intake over the lifter valley, you will still need an air intake somewhere.

If you are determined to use the intake, assuming an SBC, you might be able to use the spot at the front where the oil fill tube went on older motors.
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Old 10-29-2024, 10:39 PM   #8
cadillac_al
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Re: Pcv valves

It sounds like the ol' 29 needs a 283 or small journal 327 with the old road draft/pcv system. Like kwmech said, I don't think you could find the perfect grommet to seal a hole in the intake manifold. Then you would most likely need the old style manifold with oil fill in the front for an air vent.
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Old 10-30-2024, 09:34 AM   #9
raggedjim
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Re: Pcv valves

These guys did it...
https://paceperformance.com/i-514637...e-drilled.html

The hole doesn't go into the intake runner. The hole is where the pcv will pull crankcase gases, the other end of the pcv goes to your vacuum source.

This would also work on the newer intakes with a valve cover mounted breather.

If you drill the hole yourself you can use this style grommet, it is baffled to prevent the pcv from pulling oil. https://www.summitracing.com/parts/m...saAv6IEALw_wcB

Good luck, Rg
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Last edited by raggedjim; 10-30-2024 at 09:54 AM.
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Old 10-31-2024, 12:25 AM   #10
Ziegelsteinfaust
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Re: Pcv valves

Quote:
Originally Posted by raggedjim View Post
These guys did it...
https://paceperformance.com/i-514637...e-drilled.html

The hole doesn't go into the intake runner. The hole is where the pcv will pull crankcase gases, the other end of the pcv goes to your vacuum source.

This would also work on the newer intakes with a valve cover mounted breather.

If you drill the hole yourself you can use this style grommet, it is baffled to prevent the pcv from pulling oil. https://www.summitracing.com/parts/m...saAv6IEALw_wcB

Good luck, Rg
Thanks

I never seen those baffle grommets before
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Old 10-31-2024, 09:22 AM   #11
raggedjim
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Re: Pcv valves

Quote:
Originally Posted by Ziegelsteinfaust View Post
Thanks

I never seen those baffle grommets before
I've never used one but I am researching doing this on my truck.

Good luck, Rg
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