Each cylinder has 2 intake valves and 2 exhaust valves. Intake and exhaust efficiency is increased by means of the larger total port areas.
The valves are directly opened and closed by 2 camshafts.
The intake camshaft sub-assembly is driven by a timing belt, while the exhaust camshaft sub-assembly is driven by gears on the intake camshaft sub-assembly.
Small-diameter, flat-teeth gears are used for driving the exhaust camshaft sub-assembly in order to reduce gear noise.
|*1||Timing Belt||*2||Camshaft Drive Gear|
|*3||Exhaust Camshaft Sub-assembly||*4||Intake Camshaft Sub-assembly|