Rochester Carburetor CFM - Venturi Bore Diameters
How to Identify a 750cfm or 800cfm Rochester
Looking down the primary venturi you can see what appears to be a ring around the center, notice how much larger it appears in the 750cfm carb on the left, and notice the "peanut" on the smaller ring in the 800cfm carburetor on the right.
Stage-1 uses, 75 jets, 45 primary rods, CK sec. rods, and a K hanger