Cayenne Titanium (9PA) V8-4.5L (2006)
Identification of pistons
Markings on piston crown: Replacement pistons from Porsche Parts Service are only obtainable in one dimensional group 'X' and in two weight
tolerances '+' and '-'. The weight tolerances are listed in the table.
^
Marking X appears as a large colored stamp in the center of the piston crown and as a small engraved feature -1-.
^
Marking + or - appears as a large colored stamp in the center of the piston crown and as a small engraved feature -2-.
Note: Pistons are installed as standard in three dimensional groups: I, X and II.
Pistons are installed as standard in two weight tolerances: + and -.
These data are all engraved on the piston crown. To uniquely identify a piston, it must be carefully cleaned (brass brush, ultrasonic bath). If, in spite of
very thorough cleaning, the data are unreadable, the piston must be weighed together with piston rings, piston pin and the two circlips. Thorough
cleaning (ultrasonic bath) is also absolutely essential to the weighing operation as otherwise the measurement result will be false.
1. A piston removed for repair is cleaned and identified. If it needs to be replaced, an X - piston with the identified weight tolerance + or - is ordered
as a replacement part and installed.