I purchased a cheapo Breather from E-bay and modified it for my dual carb app.
I enlarged the bottom drain (with nylon fitting) to go to engine breather box.
Then added two brass nipples down low to connect to head vents. The top 2 nipples will go to the carb air cleaners to vent off oil vapors.
I filled the upper half of the canister with a reticulated foam (open pore) that we use in fuel spray chambers to contain vapors. thus the liquid oil getting to the air cleaners will be minimized. No external vent needed.
This will mount to firewall above engine oil filler
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