BRAKE VALVE FOR ENGINE BRAKING

摘要

An engine braking system comprising backpressure valves located in the exhaust system upstream of an engine turbocharger. The valves can be adjustable knife edge flap valves or D-shaped valves situated in each passageway of a divided exhaust manifold. By using backpressure valves located upstream of the turbocharger, the adjustable valves can be closed to varying degrees to generate desired levels of backpressure while allowing exhaust gas to pass though open regions of the partially obstructed flow pathway to reach the engine turbocharger. By not completely closing the valve and not fully restricting the flow of exhaust gas to the turbine, the turbine continues to spin, the engine mass flow is not choked off, and improved brake performance will result.