I've long since lost my understanding of the Holley carb numbering system, but I'm not sure that 1.600 Venturi carb is the 950 that only flows 830. I could be wrong, because like I said, I don't buy Holley stuff. I think the only way that big Venturi could only flow 830 is if it has 1.687 throttle blades or something.
I guess I should get a new Holley catalog so I can look at what they are doing.