Carb size ?
I think the answers will vary greatly for different builds, but generally, the smaller 4 barrel Carters work well. I plan on running an 800 CFM Thermoquad on mine, but it is going to be a somewhat radical N/A slant six. I think the factory used the Carter 400 4 barrel on the Hyperpack if I am not mistaken. I think 400-500 CFM would work well on most.