This is equally spaced at 5.5" centers for performance carbs such as the 4412 carburetor!! This bolts to the top of a 6 71 or 8 71 supercharger. The carburetor bolt pattern will work for the Holley 0-4144-1 & 0-4365-1 4412 carb.

The center rib of the blower case will fall right in the middle of the center carb, it can be removed or use an air file on it to help the flow, also you can see that the equal spaced carbs put the end carbs past the edge of the case and would need some massaging as well but that's part of the game when hot rodding.