Wieand Fly Eye Question....

[mockingbird812]

My Weiand Fly Eye air cleaner has two holes on the bottom that if left unplugged would allow unfiltered air directly into the carb. Witness marks on the bottom indicate that only one of the holes was ever plugged. I still have one of the plastic plugs manufactured by "Lynx".

Why were these holes there with the option to leave them plugged or not? Was it for a PCV hook up (on a performance air cleaner)?

Thanks.