Abstract: An exhaust gas scavenging apparatus includes a series of chambers designed to actively lower the exhaust gas back pressure of an internal combustion engine. The device uses the waste energy from the exhaust system in the form of both the Venturi principle and the amplification of a pulse wave effect. The scavenging system uses a series of in-line tubes or a single tube with perforations, passing through multiple sealed chambers using the Venturi effect to lower the pressure in each chamber.