Last fall I had some 452’s in the shop that had been ported elsewhere.

2.14/1.81 valves, and more porting than is what’s done on the 346 head above. Also, the 346’s were tested with old OE 2.08/1.74 valves.

Intake:
Lift——-452/346
.100—- 67.5/69.6
.200—142.8/142.8
.300—207.6/206.8
.400—240.1/236.6
.500—256.1/251.3
.600—260.6/259.9

Exhaust:

Lift——-452/346
.100—- 57.1/56.1
.200—-111.0/106.1
.300—-150.0/140.8
.400—-167.1/170.0
.500—-170.8/185.4
.600—-174.4/193.2

With 2.14/1.81 valves in the 346 head, it would be 265-270 on the intake side and over 200 on the exhaust.
Might need a bit more work at the pinch to get to 270.