Yo! Guys, back home! Anyway, you say it's starved for fuel. Let's go step by step. First, describe starved for fuel. While in neutral, does it sputter at idle upon acceleration, or is it when the car is under load. You have to get a clear picture out. It's just like saying the car won't run: Does "won't run" mean that it cranks but won't start, or it won't crank. Likewise, starved for fuel doesn't give up much to work with. As a reslut you get a series of answeres that you have received.
(Another quite important peice of information that would help is to know whether this is a new car/set-up for you, meaning that you don't know how it ran before, or you have had the car, it ran properly before, and this is a new problem.)
To eliminate email tag, you say that you verify gas at the filter. You have ruled out such a problem with other carbs; even so, you make better headway by knowing for sure that the carb has gas. Physically check the fuel bowl for gas. (Something tells me that you have a Holley on it. I dislike Holleys, so I'm biased and, natrually would say that the Holley is the problem. If you want a car that runs, put a Quad on it.)
That manifold doesn't help. Unless there is something in the 21st century production, countless flow test have proven that Pontiac's stock manifold is the best manifoild.
Because life is complicated, let's keep it that way: Could it be a weak coil?