V8 Compound Engine: Proposal for a High Efficiency-Low Cost engine

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This project aims to develop a cost-effective, high-performance version of a standard V8 engine as an alternative to I4 or V6 engines. The engine can be produced using any existing V8 design and manufactured on the same production line, minimizing costs. In this innovative V-8 engine, one bank of cylinders (Low Pressure Cylinders) is employed for a compounding operation, receiving exhaust gases from the other bank (High Pressure Cylinders). The high pressure wave generated during H.P. Cylinder's exhaust valve opening enters the L.P. Cylinder at 90º crankshaft, producing additional work. The LP cylinder bank reduces costs and weight by eliminating the need for a camshaft, valves, spark plugs, or injectors. It operates through intake and exhaust cycles via ports in the cylinder head. A central common manifold connects both cylinder banks, with gases exiting from HP cylinders and entering LP cylinders. Secondary air supply is provided to prevent vacuum formation during HP cylinder's admission-compression cycle. The compounding process adds extra power when H.P. Cylinders are at exhaust stroke, providing a balance to the engine. Lower exhaust gas temperature and pressure result from extra expansion in L.P. Cylinders, allowing for reduced silencer backpressure. This additional expansion also completes CO and HC combustion, reducing the need for high compression ratios or ignition advance that produce NOx. As a consequence, catalyst requirements at exhaust are minimized, further decreasing backpressure.