Hi guys, I got a question about the c4 i just bought, year code says 1974 on the valve body. There is a hole in it that doesn't appear in any of the other c4s I've seen, can anyone tell me what goes there?
My C4 has nothing there and it works like it is supposed to. I will have to agree with woodsnake and call it a production aid of some sort, especially if it is not threaded.