Overview: Chevrolet employed various versions of the Carter W-1 carburetor as original equipment between 1932 and 1949. In addition to these original units, Carter introduced various improvements and replacements for the W-1 carburetors. It's worth noting that these carburetors were not exclusively used by Chevrolet, as they found applications in a wide range of vehicles from different manufacturers.
1932 Chevrolet: Early passenger vehicles featured the 212s carburetor (Chevrolet 836615), later replaced by the 235s (Chevrolet 836853) mid-year. Trucks used the 222s (Chevrolet 836735) with a smaller venturi. These carburetors were Chevrolet-produced and identifiable by the cast "C" on the body. However, they are rare and best suited for show cars rather than daily drivers. Key characteristics include a high idle mixture screw, 2-hole bowl cover, 2-hole airhorn, and no distributor vacuum port.
1933 Chevrolet: The Chevrolet model CA used the Carter 259s (Chevrolet 837110), while the "Standard" used the Carter 260s (Chevrolet 473685). These carburetors are similar to the 1932 units but with minor calibration changes. They are also recommended for show cars rather than daily use.
1934 Chevrolet: 1934 brought a significant design change, moving the idle mixture control screw to the lower part of the throttle body, improving idle performance. Carburetors used in 1934 were the 284s (Chevrolet 837341) on the Master and the 285s (Chevrolet 837373) on the Standard. The 285s had reduced airflow. These units, while improved over the 1933 versions, are still best suited for show cars.
1935 Chevrolet: The 284s from 1934 continued to be used on early production 1935 Master cars, later replaced by the 319s (Chevrolet 837894). Fleet cars used the 321s (Chevrolet 837918). The 319s had a 3-hole airhorn for improved reliability. These units are recommended for show cars.
1936 Chevrolet: The 319s from mid-1935 was used in early 1936 and later replaced by the 334s (Chevrolet 838013) on the Master, with 335s (Chevrolet 838047) used on Fleet vehicles. The 334s introduced a new metering rod, but these units are still best suited for show cars.
1937 Chevrolet: In 1937, a major improvement was introduced with the 4-hole bowl cover, addressing a design flaw. Carburetors from 1937 onwards are more reliable and can be considered for daily drivers or show cars. The 346s (Chevrolet 838526) was used on the Master, and 358s (Chevrolet 595959) on Fleet vehicles.
1938 Chevrolet: The 1937 Fleet 358s was retained for 1938, while the 391s (Chevrolet 838682) was used on the Master. The 391s featured a 1-piece choker valve and other minor changes.
1939 Chevrolet: New carburetors, the 420s (Chevrolet 838938) for the Master and 434s (Chevrolet 838990) for Fleet vehicles, were introduced in 1939. They had design changes in the throttle shaft.
1940-1949 Chevrolet: The 1939 carburetors were carried over for the 1940 model year, and Carter continued to make modifications to improve performance and reliability through 1949. Each year brought subtle changes and improvements.
General Restoration Tips: Restoring these carburetors requires careful disassembly and the use of appropriate kits. Pay attention to problem areas like airhorn and bowl cover warpage, countershaft condition, and pump/metering rod linkage. Some parts can be reworked or repaired, but replacements are readily available for worn components.
Regarding neoprene fuel valves, be cautious when using them, as some modifications may be needed for a proper seal. Lastly, consider original Carter service instructions for guidance during restoration.
Additional Notes: This summary excludes information on replacement and military W-1 carburetors. Some replacement units, like the 569s, can serve as good replacements for daily drivers. The W-1's mechanical power system makes it easier to tune on aftermarket multiple carb setups. The 483s/574s units are recommended for such applications due to their availability, cost-effectiveness, and durability. However, the 684s, while similar, is not as recommended due to limited parts availability and higher costs.
