[gweilbaker]

Just FYI:

Carburetors fall into two types, one the unbalanced type and the other a balanced type unit. In the bowl cover of the unbalanced type carburetor, is a hole drilled to a definite dimension. It is through this hole that air flows and exerts pressure, or pushes against the gasoline in the float bowl.


The air going through the air horn has no effect on the gasoline in the float bowl of the unbalanced type of carburetor. As a result, should the air filter on the carburetor be restricted with dirt, oil, or any foreign substance the air flow into the air horn would be slowed down or reduced in volume. When this happens, the carburetor not getting sufficient flow of air runs rich, because the pressure on the fuel in the float bowl remains the same as normal,.



In the balanced type of carburetor this cannot happen. The vent hole in the bowl cover is internal and the float chamber is vented by means of a tube into the air horn. If the flow of air into the air horn is restricted, by this internal venting, the pressure on the gasoline is also restricted. Consequently, the pressure in the air horn and the pressure in the float chamber are balanced.