Abstract: Embodiments of the invention provide a supercharger including a housing with a scroll-like upper housing at one end and a gear housing at an opposite end, and an output aperture defined by the upper housing. Some embodiments include a supercharger that has a compression chamber that is at least partially surrounded by at least a portion of the upper housing. The supercharger includes an impeller at least partially positioned in the compression chamber, and a variable or interchangeable inlet extending from the housing that defines an inlet aperture fluidly coupled to the compression chamber. Some embodiments include an anti-backlash gear assembly coupled to an impeller gear of the impeller.