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The Place for Model-A Ford Carburetors

The Model B carburetor was built for original installation in Ford Model B engines from 1932 through 1934.

Model B Carburetor

Zenith Model B Carburetor
  • The Zenith carburetor, which is now commonly called the "Model B", was built for original installation in Ford Model B engines from 1932 -1934. However, some Model A Ford owners like to adapt their Model A engines with the Model B carburetors, with the expectation of obtaining additional horsepower.
  • The Model B Zenith carburetor has an .866-inch inside diameter Venturi compared to the .846 inch diameter Venturi of the Model A carburetor. The Model B carburetor input and output throats are also larger than the throats of the Model A carburetor. These changes provide greater airflows.
  • Another significant difference is that Model B has a Power Jet circuit to increase the amount of fuel supplied to the engine during acceleration and high-speed driving. This circuit is controlled by the throttle shaft position.
  • The Model B carburetor's mounting flange and bolt holes are identical to the Model A carburetor. However the flange on the Model B manifold is rotated somewhere in the range of 7 degrees, compared to a Model A manifold. Therefore, if a Model B manifold is used in a Model A with either a Model A or Model B carburetor the Model A choke rod will not align and connect properly. The choke rod will align if a Model B carburetor is mounted to a Model A manifold in a Model A. The throttle linkage will also connect with out modification. However, the fuel line will require modification as the Model B carburetor's fuel inlet connection is on the end rather than the side.
  • The Zenith, Model B carburetor works in much the same way as the Zenith, Model A carburetor (with the exception of the added Power Jet). Quite a few of the parts are interchangeable. So, much of the information found on this website on the Model A carburetor is directly relatable to the Model B carburetor.
  • Good sources of information on this Model B carburetor can be found in Resources.

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