Manley 04+ Subaru WRX STi (EJ257) 75mm DE-STROKED 99.75mm +.25mm Bore 8.5:1 Dish Piston Set w/ Rings

621002C-4

Manley pistons are machined of high strength 2618 material. Each design is lightweight yet robust enough to deliver long service life. Offset wrist pin design is utilized for quiet start-ups. Perfect ring groove to skirt squareness is achieved through our unique "one fixturing" manufacturing method that assures maximum horsepower. All pistons come with moly coated skirts. Round wire locks, premium chrome moly wrist pins, and premium steel top ring sets from Total Seal are included with every kit at no additional charge. 9310 alloy upgraded wrist pins are available. Recommended clearance: .003" for mildly boosted and .0035" for highly boosted measured .850" (79/83mm Strokes) and 1.100" (75mm Stroke) from the bottom of the oil ring groove.

Manley Subaru EJ257 pistons now include Napier style second rings and higher tension oil rings (by Total Seal) for superior oil control.

Features:

• 2618 alloy for maximum high temperature strength and fatigue resistance.
• "Contour forgings" provide the optimum balance between strength and weight with no grain-interrupting internal milling.
• Proprietary multi-step top ring groove machining process assures optimum control of the groove's size, geometry, flatness, and finish.
• All final turning is performed in one fixturing resulting in complete squareness of rings to the cylinder wall.
• Federal Form-Scan gauging validates ideal skirt indexing to pinhole and skirt-to-skirt polarity.
• Value - added features such as a pressure balance groove included in all series.
• Precise pinhole machining results in an exact compression distance as well as precise lock ring groove spacing, size, and concentricity.

Specifications:

• Bore Size (mm): 99.75
• Over Size: +.25mm
• Rod Length: 5.137"
• Stroke: 75
• Comp. Distance: 1.285"
• Dome Volume (cc): -21
• Cylinder: 51
• Comp. Ratio: 8.5
• Piston Type: Dish
• Piston Wt / Gms: 434
• Included Ring Set: 46997DT-4

Includes:

• (4) Pistons
• (4) Piston Ring Sets
• (4) Wrist Pins
• (4) Wire Locks

Fitment:

• Subaru WRX | STi EJ257 2004-2014