The Autolite 4300 was a four-barrel (four venturi)

carburetor A carburetor (also spelled carburettor or carburetter) is a device used by a gasoline internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the Ventu ...

manufactured by

Autolite Autolite or Auto–Lite is an American brand of spark plugs and ignition wire sets headquartered in Cleveland, Ohio. Autolite products are sold in the United States, Canada, Mexico, and Australia. Until 2011, the Autolite brand was a part of ...

in multiple variants from 1967 through 1974. Used by both

Ford Ford commonly refers to: * Ford Motor Company, an automobile manufacturer founded by Henry Ford * Ford (crossing), a shallow crossing on a river Ford may also refer to: Ford Motor Company * Henry Ford, founder of the Ford Motor Company * Ford F ...

and

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, it was produced as an emissions-compliant replacement for the previous Autolite 4100 model, and was superseded by the Motorcraft 4350. Both the 4300A and 4300D have unique spread bore

throttle plate A throttle is a mechanism by which fluid flow is managed by construction or obstruction. An engine's power can be increased or decreased by the restriction of inlet gases (by the use of a throttle), but usually decreased. The term ''throttle'' ha ...

designs (the 4300A being much less pronounced than the 4300D), which must mate to a correspondingly configured intake manifold.

Variations

4300A, 441 CFM (1967-1969)

The 4300A, a four-barrel 441 CFM carburetor, was released in 1967, replacing the 4100 on all Fords excluding the police package 428 CID and 289 CID high-output engines.Enyeart, Jon
"The Autolite/Motorcraft 4300 and 4300D"
'' Mustang Times'', November 2009. Retrieved on 25 August 2012. 4300A 441 CFM specs:Jones, Daniel C
"4300D Carb"
''

DeTomaso E-list De Tomaso Automobili Ltd. (previously known as De Tomaso Modena SpA) is an Italian car-manufacturing company. It was founded in 1959 by Alejandro de Tomaso in Modena. It originally produced various sports prototypes and auto racing vehicles, incl ...

'', May 2003. Retrieved on 1 September 2012. * 1" primary venturi * Primary throttle bore: 1-7/16" * Secondary throttle bore: 1-9/16" The 4300A was found to run too lean for the 390 CID engines, resulting in the development of the 600 CFM 4300A in 1968.Smart, Jim
"How to identify Mustang Carburetors"
'' Mustang Monthly'', October 2009. Retrieved on 25 August 2012. The 441 CFM 4300A was discontinued after the 1969 model year in favor of the two-barrel Autolite 2100 carburetor.

4300A, 600 CFM (1968-1974)

A 600 CFM version of the 4300A with a 0.25" larger primary venturi and 0.20" larger primary and secondary throttle bores, was released in 1968. By 1970, it was factory supplied on most Fords equipped with the 429 and 460, in addition to vehicles with the 351 Cleveland. 4300A 600 CFM specs: * 1.25" primary venturi * Primary throttle bore: 1-9/16" * Secondary throttle bore: 1-11/16"

4300D, 715 CFM spreadbore (1971-1974)

In 1971, the 715 CFM 4300D was introduced, featuring a much more pronounced spreadbore design with the same primary venturi and primary throttle bore as the 600 CFM 4300A but a much larger 2" secondary throttle bore. Produced through 1974, it is incompatible with other spreadbore intake designs. 4300D 715 CFM specs: * 1.25" primary venturi * Primary throttle bore: 1-9/16" * Secondary throttle bore: 2"

Motorcraft 4350

The 4300D was replaced by the Motorcraft 4350 carburetor in 1975.

Criticism and improvements

Both variants of the 4300 have been criticized for poor acceleration, rough operation, and a potential for fire due to a poor fuel inlet design.Pony Carburetor
"Autolite 4300"
, '' Pony Carburetors'' Retrieved on 25 August 2012. This negative reputation is not universally accepted amongst users of these carburetors.

References

{{reflist Carburettors Ford Motor Company