Numbers on pistons

[Owen:s]

Any1 know what they represent or indicate thanks

 

[mr.pink87]

Part number? Diameter? What kind of numbers are they?

 

[Owen:s]

117.5 c5
B5 347.7
Defo not part numbers.

 

[sophiesdad]

used by manufacturers

Direction of piston flywheel end​

Piston category (2 - 3) or (B - C)
Piston axis of symmetry​

Gudgeon pin hole axis
Offset between gudgeon pin hole axis and piston axis of symmetry​

Engine suffix (the own number to correspond to a paticular enine suffix)​

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