Abstract: Turbocharger or supercharger for an internal combustion engine, which includes an exhaust turbine in the engine exhaust gas stream and a compressor in the fuel/air mixture stream between the fuel/air source and the intake manifold for boosting the intake manifold pressure; a dedicated recirculation loop connecting the compressor output with its input and a recirculation control valve disposed in the recirculation loop for controlling the amount of airlfow in the recirculation loop. The recirculation control valve is linked to the engine power control linkage such that at high power, the recirculation is blocked while at low power the recirculation is unrestricted. As a result, at low power the turbine and compressor is kept running at a relatively high RPM due to the recirculation loop being open, and at suddenly increased power demand, power boost is immediately available without turbo lag due to the closing of the recirculation loop.