This slight opening and closing creates a shock wave that aids {HEAD ~ the atomizing air and fuel mixing} in {TAIL ~ the intake system} prior to normal intake valve opening and enhances the scavenging of combustion gases during the exhaust cycle 
This slight opening and closing creates a shock wave that aids { HEAD ~ the atomizing air and fuel mixing } in { TAIL ~ the intake system } prior to normal intake valve opening and enhances the scavenging of combustion gases during the exhaust cycle
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