Dimples reduce turbulence in a Flowport
If golf balls did not have a dimpled surface, even Tiger Woods would have difficulty reaching 200 metres with his best drive. Dimples improve the way the air flows over the surface of any object. In the case of reflex ports, they offer a significant improvement over simply flaring the port ends by reducing air flow turbulence at each end of the port; so you get less chuffing noise and less compression at high sound levels.