If your not married to that 273 block, 318 blocks are given away and considering you may not be using the "10.5:1" Egge pistons (debatable CR) and may go with a flat top, youll find many more flat top 318 pistons available. Changing cams, intake and exhaust just makes keeping the 273 size the head scratcher. you can dress up the 318 all you want with 273 badges and no one will know. The thing with the 273 was its high revving 4bbl option (and the small V8 it was designed to fit in) neither are in play now so a 318 is already now a big bored 273. No one builds a 260 Ford, they all build 289/302's. Unless your building a 4bbl 273, Id go with a 318 to start. JMHO.
