Also think about what you want to do street or race etc. That will determine a direction. For me ,I am in the middle of a refresh of one of my 340s. I would like to be as close as I can get to a stock 68 340 4 speed engine. I am not sure the factory cam grind is available so I am open to suggestions on a cam, but I don't want anything too aggressive or that needs anything more than stock style valve springs. Point is to know what you want and how far to go.