The "sewing machine whistle" is a distinct cyclic noise cause by unstable compressor operating conditions known as compressor surge. This aerodynamic instability is the most noticeable during a rapid lift of the throttle, following operation at full boost.

turbobygarrett.com

TurboMaster is a company devoted exclusively to the turbocharger's business since its foundation in 1980, i.e. more than 35 years of experience, knowledge and service backing us up, all of them available for your power needs. 
Distributoren der weltbesten Marken GARRETT, HOLSET, HITACHI und TIAL.