Correct breather cap for 73 Road Runner w/ big block?

pdiz

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I have a '73 Road Runner with a 400 and dual-snorkel air cleaner. I have vintage Holley cast aluminum valve covers and I'm trying to make them as "stock" as possible (in function, anyway). So far I have plumbed the PCV directly into the driver's side valve cover (no PCV housing or anything, it's directly in the valve cover with a grommet) and going to the carburetor, and I installed Moroso baffles underneath which incidentally had the same bolt-hole spacing. All good.

For the passenger side, what breather cap was correct for the 400; one, two, or three prong? Car is in California, so not sure if this makes a difference, and it doesn't need to be "restored" to California "standards", if that makes sense, I just want to make the car like the majority were in other states. The FSM only shows the one breather cap nipple that goes to the air cleaner, although the diagram seems very generic and doesn't seem to cover all the deviations, if there were any.

Second question, for those with the three-prong breather cap, where do all the connections go other than the big one to the air cleaner? I looked at the charcoal canister that goes to the tank, I looked at the carburetor fittings, but I'm just not finding it in the manual. Did the manual not show all the deviations?

Thanks.
 
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pdiz

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I'm guessing for the three-prong breather, it's all N95 emissions stuff which is probably long gone, and I'll just bypass it with a simple breather. lol
 

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