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PKRWUD · 08-14-2001, 06:27 PM

First, let me clarify something. The term "manifold vacuum" means unrestricted vacuum that is taken from anywhere below the throttle plate(s). It designates the source of the vacuum, not where the vacuum hose goes to. Your power brake booster has manifold vacuum applied to it. So does your fuel pressure regulator, etc. Your PCV valve requires manifold vacuum to re-route the blow-by back into the combustion chamber. Blow by gasses carry with them traces of oil, which is unavoidable, but, to lessen the amount of oil entering the intake, manufacturers place a baffle and a filter in the PCV route. That is why valve covers have a baffle underneath the breathers, and why all the carburetor equipped factory air cleaners had that funny foam wedge stuck to the inside of the air cleaner where the PCV hose entered. Ford places the baffle below their choice of locations for the PCV valve, the rear of the intake manifold, and they also insert a filter in there. Those two items, when clean, prevent 99% of the oil from reaching the intake. Do you have other options? Of course you do. You can block off the factory location and install a PCV valve into a valve cover breather hole, using a proper sized grommet. Make sure you insert a foam filter underneath the valve first. As long as there is a baffle and a filter, you should be fine. There are other ways to get rid of the blow-by as well, including having it routed directly into the exhaust, but that should never be used on a street driven vehicle. Talk to your mechanic about installing a PCV valve in the valve cover, but don't forget the baffle and the filter, otherwise you'll just be sucking oil into your intake.

Take care
~Chris

------------------
Retired Moderator
MustangNet

My site: JimPorterRacing

RACECAR spelled backwards is RACECAR

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08-14-2001, 06:27 PM	#12
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	First, let me clarify something. The term "manifold vacuum" means unrestricted vacuum that is taken from anywhere below the throttle plate(s). It designates the source of the vacuum, not where the vacuum hose goes to. Your power brake booster has manifold vacuum applied to it. So does your fuel pressure regulator, etc. Your PCV valve requires manifold vacuum to re-route the blow-by back into the combustion chamber. Blow by gasses carry with them traces of oil, which is unavoidable, but, to lessen the amount of oil entering the intake, manufacturers place a baffle and a filter in the PCV route. That is why valve covers have a baffle underneath the breathers, and why all the carburetor equipped factory air cleaners had that funny foam wedge stuck to the inside of the air cleaner where the PCV hose entered. Ford places the baffle below their choice of locations for the PCV valve, the rear of the intake manifold, and they also insert a filter in there. Those two items, when clean, prevent 99% of the oil from reaching the intake. Do you have other options? Of course you do. You can block off the factory location and install a PCV valve into a valve cover breather hole, using a proper sized grommet. Make sure you insert a foam filter underneath the valve first. As long as there is a baffle and a filter, you should be fine. There are other ways to get rid of the blow-by as well, including having it routed directly into the exhaust, but that should never be used on a street driven vehicle. Talk to your mechanic about installing a PCV valve in the valve cover, but don't forget the baffle and the filter, otherwise you'll just be sucking oil into your intake. Take care ~Chris ------------------ Retired Moderator MustangNet My site: JimPorterRacing RACECAR spelled backwards is RACECAR HEY !!! Are you ASE Certified ??? If you are, ask me about iATN. The best tool you'll ever have, and it's free !!!