NOVELTY - An aftermarket motor vehicle air filtration system includes a filter housing and a battery tray (70) formed integrally with the housing and extending along a longitudinal axis parallel to one of housing walls (42, 44, 46) so that a battery placed on the tray is positioned within the housing. An air intake tube (50) is secured to the housing. A filter element (60) extends upstream from a base portion alongside the battery and above a floor to a top portion. The filter element shares common air space with the battery within the housing to allow for an increase in volumetric filter flow rate.    USE - For motorized vehicles, e.g. Ford F-Series trucks having 7.3 L V8 turbo-diesel engine.    ADVANTAGE - The filtration system improves engine performance by increasing horsepower, torque and/or fuel economy.    DETAILED DESCRIPTION - An aftermarket motor vehicle air filtration system includes a filter housing having adjacent walls extending upwardly from a floor (48) to an upper edge with one of the walls defining an air outlet port. A battery tray is formed integrally with the housing and extends along a longitudinal axis parallel to one of the walls so that a battery placed on the tray is positioned within the housing. An air intake tube is secured to the housing. The air intake tube has an upstream end projecting through the air outlet port and a downstream end through which filtered air passes on route to an air intake of an internal combustion engine. A filter element having base and top portions extends upstream from the base portion alongside the battery positioned on the tray and above the floor to the top portion. The filter element shares a common air space with the battery within the housing to allow for an increase in the volumetric filter flow rate over the flow rate achievable in the stock system. The base portion is connected to the upstream end of air intake tube.    DESCRIPTION OF DRAWING(S) - The figure is a perspective view of an air filtration system.    Housing walls (42, 44, 46)    Housing floor (48)    Ramp (49)    Air intake tube (50)    Mounting flange (52)    Filter element (60)    Battery tray (70)    Tabs (71)    Ribs (76)