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Subaru Impreza STI IHI VF39 turbine housing wastegate porting

Pavel’s Racing Engines is proud to offer turbine housing porting and blending services for your turbochargers. This is a purposeful modification and not just another thing to add to your “modifications list”. Main purpose of turbine housing porting is to reshape the inlet and remove airflow restriction to the internal wastegate. Restrictive wastegate castings can lead to boost creep and boost spike conditions at different engine operating conditions. We blend and reshape the turbine housing to increase flow to the wastegate valve and improve boost pressure control. Porting of the turbine housing, as typically done by tuner shops, can actually be detrimental to performance and durability of the turbocharger. OEM manufacturers spend millions of dollars on research and development of the optimal housing size and shape. Porting and removing of material will increase housing inner dimensions and can lead to premature cracking. We blend casting marks of the turbine housing and polish it. Only material removal we do benefits wastegate exhaust gas flow characteristics.


Pictures of a blended and modified wastegate opening on a Subaru Impreza WRX IHI VF39 turbo: