I just bought a finned valley cover on ebay, and i noticed it was missing the hole that is connected to a tube on the back of the original. Will this cause any problems?
I'm guessing that you have an older nailhead that ventilated the crankcase with a "road draft tube" vs. a PCV system. Acrankcase has to be ventilated or it will pressurize and cause all sorts of nasty things to happen. In the "old days" there was a breather on the valve cover (or somewhere) for air in, and a tube sticking out of the engine somewhere (like the valley cover) that ended up pointing down under the car for air out. It had a diagonal cut on the end so the wind (road draft) flowing past it would scavange the air out of the engine. To answer your question, one way or another, yopu have to ventilate the motor. With a solid valley cover, you need a breather on the oil intake on the valve cover and a PCV system to pull the air out. Look at a later model nailhead to engineer it. It's easier that way. Good Luck.
