The VNT stands for Variable Nozzle Turbine, which means that the internal technology the internal technology of the turbocharger uses variable vanes to control the exhaust flow against the turbine blades.
These types of turbos are also sometimes referred to as Variable-Geometry Turbochargers(as with Holset’s VGT Turbos) or Variable-Turbine Geometry Turbochargers(as with Borgwarner’s VTG Turbos).
These turbos are highly efficient and very complex, this is because the variable vanes act as a sophisticated Engine Management System used for minimizingturbo lag which allows for an increase in throttle responsiveness, particularly at low engine speeds.
This is done by altering the direction and speed in which the gasses impact with the turbine wheel.
This type of technology is used by many turbocharger manufacturers including; BorgWarner, Holset, IHI, Cummins and Mitsibushibut it is most commonly associated with Garrett, the world’s leading turbocharger manufacturer.
Garrett’s method of incorporating “a ring of small movable vanes around the turbine wheel” is featured in millions of passenger cars and vans around the world today.