Carburetor - ROCHESTER E4MC/E4ME: Description: Notes

The E4MC and E4ME carburetors are of a 2-stage, downdraft design. The secondary circuit is composed of 2 large throttle bores, using the air valve principle, in which fuel is metered in direct proportion to the amount of air passing through the secondary throttle bores. A baffle is attached to the secondary side of the air horn, above the main well bleed tubes. This deflects incoming air to improve secondary nozzle operation on heavy acceleration.

The E4MC carburetor uses an air heated choke assembly; the E4ME, an electrically-actuated choke assembly. All E4MC and most E4ME models have 2 vacuum break diaphragm assemblies, primary and secondary, while some E4ME models have only primary vacuum break assembly.

Chrysler Motors vehicles use the Electronic Spark Control System (ESC). All carburetors are equipped with an electrically-actuated mixture control solenoid mounted in the float bowl. For all applications, fuel metering is controlled by stepped metering rods that operate in removable jets.

All models include tamper-resistant factory settings of the mixture control solenoid rich limit stop and lean mixture screw, idle air bleed valve, TPS, ILC, ISS and idle mixture screws. DO NOT  adjust these except during major overhaul or replacement of air horn, float bowl or throttle body. Both electric and hot air chokes have riveted covers which must not be removed except for major overhaul. The Chrysler Motors engine uses an ISS for controlling idle speed.