best way to make it breathe

looking for the most bang for my buck. which heads are the best as far as pulling them off at the junk yard and modifying and which are the best out of the box get to keep the same intake and headers? I'm looking start a progressive build right now I want to build a stock 360 crank street and strip 30 over. looking to build anywhere from 300 to 350 hp. I want to put the best heads I can on there I don't mind hunting them down. Eventually I would like to build a 408 but that's not for another 3 yrs down the road.