Skip to main content...

Model-A.org

The Place for Model-A Ford Carburetors

A number of alternatives to the Zenith, Model A Ford carburetor became available for use during the Depression era. In addition to the carburetor used on Model B Fords, there were many other after market carburetors.

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.

ˆ Top of Page

Other Model A Carburetors

  • Over the years, numerous articles have been published in the Model A Ford Club of America's "Restorer" magazines about carburetors, which were used in the place of original equipment Zenith carburetors, on Model A Fords. There were many carburetors that came on the market to fill the need when consumers found that a standard Zenith wasn't available or they were too expensive. Most of these "Off Brand and Model" carburetors were made during the Depression or World War II eras.
  • If you have one of these old carburetors and are looking for a little information about it, here is a list of carburetors and manufacturers, which I have found mentioned in articles. Modern day manufactured carburetors, which are sometimes applied to Model A Fords are not listed here.

ˆ Top of Page