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Old 04-26-2008, 02:43 AM
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the most efficient PCV valve setup

I'm tryng to compare all options for clearing out the gasses in the engine, first I want to know if there is any way of having a breather setup that would work equal to or better then a PCV valve? but if thats not possible...

I want to know if there is a difference in efficiency between a PCV valve in the valve cover compared to in the back of the intake? does the location effect it?
and also what if I put a PCV valve in both valve covers hooked up to a Y then into the carb? how would that compare, wouldn't two clear out the engine gasses better, then one?

also when one side has a PCV valve and the other side has a breather is this for pressure perposses like air has to freely be flowing in one side to be able to flow out the other side?

~~and thanks in advance, and hopefully this thread can be the thread everyone can refer to later on with all there PCV questions~~

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Old 04-26-2008, 04:48 AM
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A PCV is basically a metered vacuum leak that pulls blowby gasses from the crankcase. Running two isn't advised and I'll tell you why. PCV valves are metered by a weighted valve inside. They are calibrated to respond to a certain vacuum. If you use two and split the lines, they will each receive half the vacuum signal and therefore might not properly open when necessary.

The best way of using a PCV is to use it in a symmetrical way. If you put the PCV in one valve cover, put the breather in the other. If the PCV is on the manifold, put a breather in each valve cover.... but only use one PCV.
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Old 04-26-2008, 05:39 AM
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good answer curtis!

it's also wise to use the pcv in a close to normal/stock configuration because the carb was engineered to include the expected "vacuum leak" cfm values to determine fuel metering...

what are you trying to do?
make the motor more "purdy"?
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Old 04-26-2008, 02:11 PM
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ok, thats what i thought. one works better then two otherwise we would've seen alot of people already doing it.

but, which do you think is better, PCV in one valve cover and a breather in the other, or a PCV in the intake and a breather in both valve covers?

well yea I really don't like the way PCV valves look on an engine at all, but mostly I like to do things the best I can to make my engine run at its best and as long as it can, so thinking the more I clear out the crankcase gasses the better it will be.

thanks
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Old 04-26-2008, 02:14 PM
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I think the valve cover must work better since every major manufacturer uses them there. Older cars had them in the valley, but there must be some benefit to having them in the valve covers.

I know that there is less chance of sucking oil from the valve cover since its not subject to crazy flying oil.
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Old 04-26-2008, 02:52 PM
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Quote:
Originally Posted by curtis73
I think the valve cover must work better since every major manufacturer uses them there. Older cars had them in the valley, but there must be some benefit to having them in the valve covers.

I know that there is less chance of sucking oil from the valve cover since its not subject to crazy flying oil.

Yep..................what Curtis says. He da man!
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