what heads to run on a 273
the '64 273 head was a heart shape chamber, after that they were kinda closed but actually had a lil concave/wedge 'so to speak' to that side of the chamber.
and unless you are lower than the factory 273's 9.1 or 8.8...flow will trump the minor half a point 'if even that' that u might gain.
flame hardend seats arent as good nor do they last like a real pressed in seat.-fact
and who's to say you can find them cheap and still runable.
spending 500 bucks or more for 5 hp 'if even that' is joke.
put this in perspective.
if he's stuck with the old bolt pattern and cant find a performance intake and the heads are shot to hell.....then i can see some advantage , but only in wider parts expansion to select from.
ever hear a closed chamber actually shrouds the valve more and effects flow as well?