Certainly, but for what? Well, quite simply to increase the volume of gas sucked in during intake, i.e. when the piston goes down into the cylinder and sucks in the gas mixture (and the same for the exhaust when the piston is raised to remove the burnt gases). Indeed, for a cylinder diameter (bore) of 81 mm for example, you can accommodate 2 valves of 40 and 33.1 mm (Golf 2 GTi 1.8 l) or 4 valves of 32.7 and 28.7 mm (Golf 2 GTi 1.8 16S) in the cylinder head, for example, 2 GTi 1.8 16S valves, i.e. intake + exhaust opening areas of 21.16 cm2 and 29.71 cm2 respectively. The 4 small valves open a larger passage for the gases which results in an increase in the power delivered by the engine.

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