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451_029
451_028
Pistons and conrods
During the development of the box piston*, special emphasis was
given to low oil consumption and low weight. The box piston is
made of a highly heat-resistant alloy and has a cast-in ring land for
the upper piston ring. Due to the high load to which it is sub-
jected, it has asymmetrical skirts and bevelled box walls on the
thrust and counter-thrust sides.
The conrod is manufactured as a forged crack conrod without a
deep bore. The pin on the small-end side of the conrod is
22 millimetres in diameter, and the bearing is made from lead-
free materials.
Enlargement of the gudgeon pin diameter to 22 millimetres
Widening of the small-end eye
Optimised skirt geometry with noticeably enlarged cross-section
Use of M9 conrod bolts
Reinforced threads
No deep bore
Mini headland rings
N1 – asymmetrical and spherical, steel nitrided + PVD*
N2 – taper-face piston ring
N3 – DSF ring* with tapered lands