Wiseco K618M77 77mm 8.5:1 Forged Piston Set for 02-06 MINI Cooper S Tritec 1.6L

Engine Fitment

• Tritec 1.6L 16V Supercharged (W11B16A -- R53 engine code)

Vehicle Fitment

• 2002-2006 MINI Cooper S (R53, 1.6L Supercharged)
• 2002-2006 MINI Cooper S JCW (R53, 1.6L Supercharged)
• 2002-2006 MINI Cooper S MC40 (R53, 1.6L Supercharged)

Fitment Notes

• Standard bore (77.00mm) -- no cylinder machining required at stock bore
• 8.5:1 compression ratio -- suitable for supercharged and turbocharged conversions
• Piston-to-valve clearance must be verified during assembly
• Cylinder boring and honing recommended for optimal ring seal even at standard bore
• Set of 4 pistons -- full engine set
• Not CARB legal

Features

• Wiseco Sport Compact series -- dedicated forgings for each application
• 2618 aerospace alloy -- superior strength for boosted applications
• Flat top crown -- 0cc, 8.5:1 compression ratio
• ArmorGlide skirt coating -- friction reduction and wear resistance
• Specially designed valve pockets -- maximizes valve clearance
• Steel nitride/Napier XX rings -- superior ring seal and oil control
• Complex skirt profile -- reduced friction, optimal ring seal
• Strutted forging -- improved piston skirt strength
• Engineered, forged, and machined in the USA

Specifications

• Series: Sport Compact
• Bore diameter: 77.00mm (3.031")
• Bore oversize: Standard
• Crown style: Flat top
• Crown volume: 0cc
• Compression ratio: 8.5:1
• Compression height: 26.5mm (1.043")
• Stroke: 85.8mm (3.378")
• Rod length: 131.5mm (5.177")
• Wrist pin diameter: 21mm
• Wrist pin part number: S624
• Replacement ring set: 7700XX
• Piston weight: 246g
• Material: 2618 aerospace aluminum alloy
• Skirt coating: ArmorGlide
• Quantity: Set of 4 pistons
• Rings included: Yes (steel nitride/Napier XX)
• Wrist pins included: Yes (S624)
• Locks included: Yes

Included Components

• 4x Wiseco forged pistons (77.00mm)
• 4x Ring sets (steel nitride/Napier XX)
• 4x 21mm wrist pins (S624)
• Wrist pin locks

Product Description

The Wiseco K618M77 is a Sport Compact series set of four forged pistons for the 2002-2006 MINI Cooper S R53 with the Tritec 1.6L 16-valve supercharged engine, at standard 77mm bore and 8.5:1 compression ratio. The flat top, 0cc crown design reduces the factory compression ratio from the R53's stock 8.3:1 slightly lower for improved headroom under forced induction -- making this the choice for builders converting from the factory supercharger to a turbocharger or upgrading the supercharger for significantly more boost where detonation control is critical.

Wiseco's Sport Compact pistons use dedicated application-specific forgings in 2618 aerospace aluminum, which is stronger and more ductile under thermal stress than the 4032 alloy used in economy piston sets. ArmorGlide skirt coating reduces friction during cold starts and throughout service life. Specially designed valve pockets provide clearance for the R53's 16-valve head layout. Steel nitride/Napier XX rings provide excellent ring seal with minimal friction. Rings, pins (S624), and locks are included. Engineered, forged, and machined in the USA.