I'll get you a pic of the intake ports real soon, but they looked rather stockish to me. The runners are a bit larger than the ports and round, obviously. My brother got this intake from a guy in Canada, and he had an additional lynx triple carb manifold that he wanted to get rid of. Don't know if it's still available.
Performance, I don't know much about that for the /6. The original BBD delivered about the same volume of fuel to the outside of the manifold that it did to the engine.
The difference in weight for headers/aluminum intake/3xcarbs versus the original parts is staggering!
Maybe slantsixdan will show up and inform