Injecting prior to turbo comp' impellers

[SaabTuner]

I'd say that probably constitutes a big portion of it.

Also when the air enters the scroll, or vane, diffuser section the velocity pressure is converted to static pressure by slowing the air back down. This involves a lot of small eddie currents in the air associated with fluid vorticity. Generally vorticity ends up dispersing into heat.

Adrian~