The stock valves are the same size as the Pontiac 389, 1.92" intake and 1.60" exhaust, but the ones pictured are probably 1.94" intake with the 1.60" exhaust. I don't recall off hand what it flowed, I just remember that it picked up a ton of flow by unshrouding the intake valve.
Here is a picture of the un-ported chamber and valve size. Both these pictures are from the engine I'm putting together, basically cleaned up the parts (hot tanked the head and checked for cracks)