Manley Performance Pistons

Fits 2004+ Subaru WRX STi with EJ257 engine

Part #: 621102C-4

Overview

The Manley Platinum Series piston set is designed for high-performance Subaru WRX STi enthusiasts and professional engine builders seeking durability and precision. Crafted from 2618 alloy forgings, these pistons deliver exceptional strength and thermal stability, making them ideal for turbocharged applications and aggressive tuning. The set features proven cam and barrel skirt profiles, ensuring optimal fitment and reliable operation under demanding conditions. With moly skirt coatings on select part numbers, these pistons help reduce friction and wear, supporting long-term engine integrity and consistent performance. Whether you're building a high-horsepower street machine or a track-ready rally car, these pistons are engineered to withstand the rigors of high-stress driving. Their precise dimensions, including a 75mm bore and a +0.25mm oversize, are tailored for the EJ257 engine, providing a perfect fit and efficient combustion. The inclusion of tool steel wrist pins further enhances durability, ensuring your engine maintains peak performance over countless miles and laps.

Key Features

Designed with advanced materials and engineering, these pistons offer:

• Forged 2618 alloy construction for superior strength and thermal expansion control
• Proven cam and barrel skirt profiles for optimal piston stability
• Tool steel wrist pins for enhanced durability and reliability
• Moly skirt coatings on select part numbers to reduce friction and wear
• 75mm bore with +0.25mm oversize for precise engine fitment
• Optimized dish design with a 9.8:1 compression ratio for performance tuning
• Engineered specifically for turbocharged Subaru EJ257 engines

Construction & Design

These pistons feature high-quality forging processes using 2618 aluminum alloy, known for its excellent strength-to-weight ratio and thermal properties. The moly skirt coatings are applied to reduce friction and improve wear resistance, supporting engine longevity. The precise machining and profiling ensure a perfect fit within the engine block, promoting efficient combustion and consistent power delivery.

Driving Feel & Feedback

Built to support high-performance applications, these pistons help your engine respond more effectively to tuning and boost pressures. They contribute to smoother operation under high RPMs and aggressive driving, providing confidence and reliability during spirited driving or competitive racing.

Installation & Fitment

Designed specifically for the 2004 and newer Subaru WRX STi with the EJ257 engine, these pistons are intended for professional assembly or experienced engine builders. Proper installation requires attention to detail and precise machining to ensure optimal performance and longevity.

What’s Included

This piston set includes all necessary pistons, moly-coated skirts, and tool steel wrist pins for a complete upgrade. Additional hardware or components are not included but may be required based on your engine build.