Tidbits off the Internet for the Zenith 28 clone made in Argentina:
1.) 200 to 300 C.I. engines.
2.) 38 mm (1.5") throttle bore. Unlike Carter and Rochester, this carburetor has a removable venturi sleeve similar to the Zenith 28/228. I wish Daytona would share the sleeve diameter. This carburetor mounted on a 261 intake manifold will be 1.5" opening up to 1-11/16?". (My first thought, flow turbulence?)
3.) On a Jeep forum, a member contacted Daytonparts.com and a salesman made the statement that, "Our Daytona Universal replacement 1bbl carburetor will flow up to 195 cfm." Unfortunately it wasn't stated if that spec was @ 1.5" or 3.0" Hg. Note: At 1.5" Hg., a previous old posting here (May 55 Hot Rod) says 182 cfm was measured on the Rochester B made for the 261.
4.) There are options, that only a retail business can purchase, but these were not described.
5.) The manual says the adjustable main jet is preset for most engines for a correct fuel/air ratio. (My thought, yeah and bullfrogs have wings). For altitudes above 3500ft, follow the adjustment procedure (as described). Some owners have reported, at lower altitudes, they had to drive a distance, stop, re-tweak one revolution then repeat until it ran best. Last step was readjust idle speed to OEM spec.
Personally I would avoid buying any Chinese made carburetors (automobile, string weeder, chainsaw etc.) especially off of ebay. There is no quality control.
Buy from a USA company (even if they import) that will provide timely replacement parts and have good technical support. A business that will take it when stuff hits the fan.
