Manley Performance Platinum Series Single Piston for Subaru WRX STi EJ257 99.5mm Bore, Grade B

Description

The Manley Performance Platinum Series single piston for Subaru WRX STi EJ257 engines offers exceptional strength and durability for high-performance applications. Crafted from domestic 2618 alloy forgings, this piston ensures superior tensile strength and thermal stability, making it ideal for demanding tuning and racing environments. The piston features precision-machined cam and barrel (skirt) profiles designed to generate significant power while maintaining gentle contact with the cylinder walls, promoting longevity and consistent performance. Including moly skirt coatings on select part numbers, these pistons reduce friction and wear, further enhancing engine durability.
The piston is equipped with chrome moly wrist pins as standard, providing reliable linkage between the piston and connecting rod. For added robustness, certain SKUs offer upgraded wrist pins made from 9310 or Turbo Tuff/DLC alloys, catering to high-stress applications. Strict manufacturing standards govern the ring lands and grooves, ensuring optimal ring seal for increased compression, power, and efficiency. Manley’s unique fixturing process allows for skirt turning and ring groove machining in a single operation, guaranteeing precise ring-to-skirt squareness and superior sealing performance. This piston also features a 79mm stroke and a 99.5mm bore, designed specifically for Subaru’s EJ257 engine architecture.
Designed for professional engine builders and tuners, this piston is a reliable choice for those seeking to maximize power output while maintaining engine integrity. It is not CARB approved, and acknowledgment of Prop 65 compliance is required before installation. Whether building a high-performance street or race engine, the Manley Platinum Series piston delivers consistent, high-quality results that meet the demands of modern tuning projects.

Features:

• 2618 alloy forgings for superior strength and performance

• Cam and barrel (skirt) profiles optimized for power and engine longevity

• Chrome moly wrist pins standard, with optional upgraded alloys

• Exacting ring lands and grooves for enhanced ring seal and power

• Unique fixturing for precise skirt turning and ring groove machining