what do i have? junk?

I started tearing my motor down and trying to see if what I have is junk or can be used. I am building a street car but I want some good hp. Also I have some surface rust on the lifters is that something that can be cleaned off? I mostly want to know if pistons are a decent one and are the valves a good size. once I pull pistons I can find out what they are...:prayer: