A turbocharger , comprising: a turbine housing and a turbine wheel mounted in the turbine housing and connected to a rotatable shaft for rotation therewith, the turbine housing receiving exhaust gas and supplying the exhaust gas to the turbine wheel ; a centrifugal compressor assembly comprising a compressor housing and a compressor wheel mounted in the compressor housing and connected to the rotatable shaft for rotation therewith, the compressor wheel having blades and defining an inducer portion , the compressor housing having an air inlet wall defining an air inlet for leading air generally axially into the compressor wheel , the compressor housing further defining a volute for receiving compressed air discharged generally radially outwardly from the compressor wheel ; and a compressor inlet-adjustment mechanism disposed in the air inlet of the compressor housing and pivotable radially inwardly and radially outwardly between an open position and a closed position, the inlet-adjustment mechanism comprising a plurality of blades disposed about the air inlet and each pivotable about one end of the blade , the blades pivoting radially inwardly through a slot in the air inlet wall when the blades are in the closed position so as to form an orifice of reduced diameter relative to a nominal diameter of the inlet , wherein the blades are coplanar and respective edge portions of adjacent blades have complementing shapes configured to allow said adjacent blades to partially overlap when the blades are pivoted radially inwardly from the closed position to a super-closed position in which the blades form an orifice of further-reduced diameter relative to that of the closed position. a turbine housing and a turbine wheel mounted in the turbine housing and connected to a rotatable shaft for rotation therewith, the turbine housing receiving exhaust gas and supplying the exhaust gas to the turbine wheel ; a centrifugal compressor assembly comprising a compressor housing and a compressor wheel mounted in the compressor housing and connected to the rotatable shaft for rotation therewith, the compressor wheel having blades and defining an inducer portion , the compressor housing having an air inlet wall defining an air inlet for leading air generally axially into the compressor wheel , the compressor housing further defining a volute for receiving compressed air discharged generally radially outwardly from the compressor wheel ; and a compressor inlet-adjustment mechanism disposed in the air inlet of the compressor housing and pivotable radially inwardly and radially outwardly between an open position and a closed position, the inlet-adjustment mechanism comprising a plurality of blades disposed about the air inlet and each pivotable about one end of the blade , the blades pivoting radially inwardly through a slot in the air inlet wall when the blades are in the closed position so as to form an orifice of reduced diameter relative to a nominal diameter of the inlet , wherein the blades are coplanar and respective edge portions of adjacent blades have complementing shapes configured to allow said adjacent blades to partially overlap when the blades are pivoted radially inwardly from the closed position to a super-closed position in which the blades form an orifice of further-reduced diameter relative to that of the closed position. <EOS>