Abstract: A V-type four-stroke cycle internal combustion engine is provided with an exhaust manifold and an air intake manifold disposed in the valley of the V-engine, and arranged one above the other. The exhaust from the cylinders passes through exhaust passages formed in the cylinder heads which discharge exhaust into the valley of the V-engine for collection in a central exhaust cavity provided in the exhaust manifold. A single exhaust discharge outlet is in communication with the central exhaust cavity for discharging exhaust therefrom. The air intake manifold includes a series of air intake passages which supply air to the cylinders from within the valley of the V-engine. A series of cylinder head intake passages are provided with openings facing the valley of the V-engine for receiving air therefrom. The exhaust manifold is preferably water jacketed for cooling exhaust prior to its discharge from the engine, and the exhaust passages provided in the cylinder heads are also water jacketed.