1. This new Street Demon is equipped with the optional phenolic center-body housing that promises cooler fuel, which should result in better driveability. The Street Demon reduces leak paths, since all the fuel is located in the center body with a gasket above the fuel level. Also, note the revised, spring-loaded air-valve secondary door. If the top portion of the carb looks clean, that's because there are no exposed fasteners; it comes apart from the bottom. The dual bolt-pattern baseplate fits both standard square flange and the spread-bore Q-jet pattern.