Granted, "size" is not everything in head ports, but "shape" can be more important. BTAIM
I suspect that in the heads orginally designed in the 1950s, that much was done "by sight" and how they looked and were suspected to perform. Getting the right balance of low-lift flow vs high-lift flow was not a real consideration, I suspect, as it came to be in more current times. It was more about total flow and .500" lift, it seemed. Huge valves were supposed to be better. Just "fill or empty the chamber" seemed to be the main orientation. But some began to notice less lower-rpm power with huge ports, which then generated the need for lower rear axle gears to reap the benefits of those huge ports.
The dynamics of the incoming air into the cyl was not a real consideration, just get it in. Similar on the exhaust side, I suspect. MANY theories of valve sizing had not been fully researched or computer-modeled. And THEN how that all related to rod length-to-stroke ratios, too! Which also relates to "piston dwell time at TDC".
Generally, even for a hp motor, intake gasket port matching, with casting clean-up in the ports, and possibly some work in the bowl area is good enough, by observation. Past that, LOTS of theories out there of what might work best, by observation.
Enjoy!
CBODY67