zenith model B carb on A

[1928Pickuppain]

so when I bought my car it had a zenith model B carb on it dose any one know the pluses or minises to running one i do have a model A tilson that I need to rebuild dose any one have any thoughts on the matter seems like the model b carb is sucking down gas .

thanks,

Derek-

 

[JoeWay]

...seems like the model b carb is sucking down gas .

thanks,

Derek-

I get 19-20 MPG on tour at 45-50 mph with a B carb on a bored A manifold.

Joe

 

[Ken/SC]

Mine gets about the same. The B model Air intake in larger than the A model Zenith.
I have let others drive my car and they say its seems to have more power. It may need to be adjusted. Also make sure it is not leaking gas in some way.

 

[Purdy Swoft]

so when I bought my car it had a zenith model B carb on it dose any one know the pluses or minises to running one i do have a model A tilson that I need to rebuild dose any one have any thoughts on the matter seems like the model b carb is sucking down gas .

thanks,

Derek-

The model B carburetor has a high speed jet and a larger throat. I ran a model B carb on my 31 coupe with a stock model A manifold and it had a noticable pickup at fifty mph. It would only gradually pickup from forty five mph with a model A zenith. They will perform a little better if the manifold is reamed out to model B size.

The model B carb is more complicated than the model A Zenith and much more complicated than the Tillotson model X or XF But will out perform either if in correct operating condition.

The Tillotson carbs are pot metal and prone to warpage and vacume leaks. I usually avoid them for that reason.

As a general rule I get around 17 mpg with a single A or B zenith while cruseing at 50 mph.

 

[Ron in Quincy]

When I rebuild the A Zenith (single venturi) I install a larger cap jet, it helps the excelleration; the cap jet I use has an orfice opening of .039. I prefer to use good original jets .

Ron