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Audi TT Quick Reference Specification Book • May 2009
Piston Ring End Gaps
Piston ring
Gap
new
Wear limit
Compression ring
mm
0.20 to 0.40
0.8
Oil scraping ring
mm
0.25 to 0.50
0.8
Piston Ring Clearance
Piston ring
Ring to groove clearance
new
Wear limit
Compression rings
mm
0.04 to 0.08
0.15
Oil scraping ring
mm
0.02 to 0.06
0.15
Piston and Cylinder Dimensions
Honing dimension
Piston diameter
Cylinder bore
diameter
Basic dimension
mm
82.465 *
82.51
* Dimension without graphite coating (thickness 0.02 mm). The graphite coating
wears away.
