Twin-turbo

The most common layout features two identical or mirrored turbochargers in parallel, each processing half of a V engine's produced exhaust through independent piping.

Parallel configurations are well suited to V6 and V8 engines since each turbocharger can be assigned to one cylinder bank, reducing the amount of exhaust piping needed.

This system is intended to overcome the limitation of large turbochargers providing insufficient boost at low RPM.

Therefore, sequential turbocharger systems provide a way to decrease turbo lag without compromising power output at high RPM.

As RPM increases, a small amount of exhaust gas is fed to the larger ("secondary") turbocharger, to bring it up to operating speed.