Abstract: A Twist-interlocking Engine Housing and Air Filter System and Method is disclosed. The filter assembly provides unequaled ease of installation and removal, as well as superior sealing between the housing and the filter assembly. For installation, the user needs only to insert the filter into the housing and then give the filter assembly a one-quarter turn or less to lock the filter assembly into the housing. There are features within the filter base that snap-locks the filter in place to resist inadvertent loosening. Finally, the housing and filter are designed so that the outer flange of the filter base is recessed into the side of the housing in order to prevent the intrusion of unwanted grime and/or fluids.

Abstract: A Vacuum Relief Assembly for I.C. Engine Intakes is disclosed. Also disclosed is a device that permits outside air into the intake tract of an internal combustion engine in the event of an excessively high vacuum condition within the intake tract. Furthermore, the device is constructed from durable materials and resists the excessive temperatures found in the engine compartment of a vehicle. Still further, the device is made from two half-cylindrical sections that mate to one another around the intake tract to form a cylindrical attachment. The method of installation enables the device to be installable onto the intake tract in situ, and without the need to cut out a section of the tract.