[miker98038]

Short answer yes. Those are widely used in the valve cover of much larger motors. But it worked fine on my 292. If the engine is fairly tight, there’s not much blowby at part throttle. At WOT, there’s no vacumn, and pressure vents thru both the PCV and the oil fill tube. That’s why I like to use a “closed” system with the fill cap plumbed to the air cleaner. I’ve always scrounged those parts for 70’s GM engines because I’m more familiar with them than 70’s Fords.