Hughes iron ram heads

I have a set of hughes iron ram heads on my 408.
I have been trying to find out the specs of my heads as far as the combustion chamber and runners cc.
Hughes 4676SP was the part number
Says They are cnc super st prepped
The invoice says they did a racing valve job
Cnc chambers
2.02 and 1.620 valves
Anyone know the comustion chamber cc and the intake/exhaust runner??????
Apparently hughes cant tell me any of the soecs i need