Here are some pictures from GM showing how the Jetfire turbocharger works. Note the white arrows that show the flow of combustion gases.
GMs Turbo Cutaway 01
GMs Turbo Cutaway 01
GMs Turbo Cutaway 02
GMs Turbo Cutaway 02
GMs Turbo Cutaway 03
GMs Turbo Cutaway 03
GMs Turbo Cutaway 04
GMs Turbo Cutaway 04
GMs Turbo Cutaway 05
GMs Turbo Cutaway 05
GMs Turbo Cutaway 06
GMs Turbo Cutaway 06
GMs Turbo Cutaway 07
GMs Turbo Cutaway 07
GMs Turbo Cutaway 08
GMs Turbo Cutaway 08
GMs Turbo Cutaway 09
GMs Turbo Cutaway 09
GMs Turbo Cutaway 10
GMs Turbo Cutaway 10