Making power out of the 318

Well, then there's zero need for people telling you to swap pistons out and other heavy work. I would concentrate on getting what's there now running as good as possible. Run a compression check. If those numbers don't look good, then you need to make some decisions. If they do, then give it a good tune up if it needs it. You can easily put a performance curve in the distributor. If you cannot, we have a member @halifaxhops who specializes in that and he can fix you up. I suggest getting what you have there running as good as it can FIRST, before you make any changes. That way you have a good base line, you will actually LEARN SOMETHING about how to work on a d tune an engine.
I guess I should’ve specified that the motor is not assembled. The motor was not assembled when I bought it and that’s how I know one of the Pistons is cracked because the previous owner was taking it apart and dropped the stock piston so I can’t do any of that and that’s why I’m building the motor because my original plan was to get one that was already running and put that in and do a very mild build but since it’s already all apart, I might as well go for It. Thank you for the suggestion though.