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'23 T-Bucket Pickup
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Yes, I removed this also. If I put breathers in both valve covers that should be plenty of vent??? Do I need a pcv valve too?
If you don’t have a PCV system pulling crankcase vapors you can expect a filthy engine compartment like we had before PCV systems. A PCV valve in one valve cover and a vented fill cap in the other will give negative pressure in the crankcase and prevent vapors from covering your engine with oil slime. Unless your engine has a bunch of blow by, you should be able to remove the filler cap and seal your hand over the filler hole while the engine is idling and feel the vacuum. If you don’t feel any vacuum and the PCV valve is good and has good vacuum to it, your engine needs freshened. Many years gone by I used a vacuum gauge that was used to check PCV efficiency. It plugged into the oil fill hole. Short version. Installing the PCV valve in a valve cover works better than putting it in the road draft hole. Just plug that hole by whatever means necessary.
 

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If you don’t have a PCV system pulling crankcase vapors you can expect a filthy engine compartment like we had before PCV systems. A PCV valve in one valve cover and a vented fill cap in the other will give negative pressure in the crankcase and prevent vapors from covering your engine with oil slime. ………….

The PCV in a performance engine can be a big vacuum leak. Another system will do the same results of venting the crank case. Same vented cap in one valve cover and the other valve cover via a hose (3/4” to 1”ID) connect to the bottom of the carburetor air cleaner base. The vacuum draw thru the carburetor will create the vacuum to draw crank case fumes into carb rather than create vacuum leak directly into manifold via carburetor base. Same results without added air leak disruption. Many original type bases already have provisions for this hose hook up.
 

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'23 T-Bucket Pickup
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1,757 Posts
The PCV in a performance engine can be a big vacuum leak. Another system will do the same results of venting the crank case. Same vented cap in one valve cover and the other valve cover via a hose (3/4” to 1”ID) connect to the bottom of the carburetor air cleaner base. The vacuum draw thru the carburetor will create the vacuum to draw crank case fumes into carb rather than create vacuum leak directly into manifold via carburetor base. Same results without added air leak disruption. Many original type bases already have provisions for this hose hook up.
I remember that many early PCV systems , such as what were on many cars and trucks that I owned, used that hose and fitting to connect one valve cover to the air cleaner and had a PCV valve in the other cover. My 1998 Silverado has that system. It’s a cleaner system than a vented oil filler. I remember earlier carbureted vehicles had a filter medium inside the air cleaner on the hose fitting. I can see the set up in my mind as clear as if I was looking at it. I’m not familiar with the big crammed low vacuum engines, but what you said makes sense. I always assumed that the shuttle in the PCV valve compensated for low vacuum conditions. I learned something today.
 
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