These carburetors have virtually no gas boil-over, for much easier starting when warm. They also have an enrichment type choke, with no flapper to get stuck. The fuel metering system is a more modern design, so smoother running is the new normal. Everything hooks up just like the originals, with the exception of the fuel line. A piece of braided fuel hose is provided to go from the metal line to the carb fitting. Core charge of $75.00 for your old carb.