Hood pins hold down the front of the hood because there is no latch like a normal car. There are 2 studs with holes in the top of them that go through small holes in the front of the hood. When the hood is closed and the pins put through the studs it holds down the hood. Used to hold the hood down for dragstrip racing, you didn't want to trust the stock latches. If you had a fiberglass hood you put four on it. Hood scoops were to get more clearence for your air intake on a large engine