Component Overview

On the turbo engine, the outlet valve is fitted with internal and external valve springs (set of valve springs) and adapted concave washers. The outlet valve in the turbo engine has the same outer dimensions as the outlet valve of the naturally aspirated engine. However, because of the sodium filling, the outlet valve in the turbo engine is lighter and the shank over the shank entries is longer. For further details, please see figures and table below entitled " VALVE DIMENSIONS  ". 

Fig 1: Exploded View Of Turbo Cylinder Head Valve Assembly

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. Intake valve (identical in naturally aspirated and turbo engines)
2. Valve-seat ring, intake
3. Valve guide
4. Lower valve-spring plate, intake
5. Valve-stem seal
6. Set of valve springs, intake (identical in naturally aspirated and turbo engines)
7. Upper valve-spring plate, intake
8. Valve collet
9. Upper valve-spring plate, outlet (different in naturally aspirated and turbo engines)
10. Set of valve springs (turbo outlet); valve spring (naturally aspirated engine outlet)
11. Lower valve-spring plate, outlet (different in naturally aspirated and turbo engines)
12. Valve-seat ring, outlet
13. Outlet valve (different in naturally aspirated and turbo engines)

Distinguishing features of outlet valve on naturally aspirated and turbo engine

1. Outlet valve - naturally aspirated engine
2. Outlet valve - turbo engine
3. Difference in shank length over shank entries
   Fig 2: Identifying Difference Between Outlet Valve On Naturally Aspirated And Turbo Engine

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.