I bought a 1979 horizon jet boat with a 455 olds, 12jc-a pump. How can I tell what impeller it has, how do I know if it needs a new one, how to service the pump, and the best question of all how to go faster? My top speed was 51. I was told it has a 650 cfm carb on the 455. It has a place divator on it. Do I need a loading great? It has these little fins on each side of the boat that are flat What are they for? Sorry for all the questions I just want to fully understand my boat. Thanks for the help