The heart of the engine is the camshaft, since it is one of the key components that dictates the engine’s power level, power band, idle quality, and other characteristics; the camshaft is used to operate poppet valves. It then consists of a cylindrical rod running the length of the cylinder bank with a number of oblong lobes protruding from it, one for each valve. The cam lobes force the valves open by pressing on the valve, or on some intermediate mechanism as they rotate.