Patent attributes
An exhaust scavenging system for an internal combustion engine including exhaust passages extending from the engine and an exhaust outlet system. A collector extends from the bundled ends of the exhaust passages to the exhaust outlet system. A central exhaust passage extends into the collector from a central position among the bundled exhaust passage outlets. The transverse cross-sectional area of the central exhaust passage through at least half of the transition collector portion from the outlet plane is not substantially less than the transverse cross-sectional area of the central exhaust passage at the outlet plane in the extended position and does decrease continuously through the transition collector portion from the outlet plane in the retracted position.
