What is the compression ratio of these pistons?

These Manley pistons have a dish design that results in a compression ratio of 8.5:1. This is a common ratio for turbocharged or supercharged engines, as it helps to prevent detonation under boost.

What material are these pistons made from?

The pistons are forged from a domestic 2618 alloy. This material is chosen for its strength and ability to withstand the high pressures and temperatures found in performance engines.

Are these pistons compatible with all EJ257 engines?

This specific piston set is designed for the 2004-2012 Subaru Impreza WRX STi with the EJ257 engine. It's always recommended to verify compatibility with your specific engine build and consult the manufacturer's fitment guide.

Specifications

Brand: Manley Performance
Part #: 622000C-4
UPC: 807298068053

Manley 04+ Subaru WRX STi (EJ257) 83mm Stroker 99.5mm STD Bore 8.5:1 Dish Piston Set with Rings

Name: Manley 04+ Subaru WRX STi (EJ257) 83mm Stroker 99.5mm STD Bore 8.5:1 Dish Piston Set with Rings
Brand: Manley Performance
SKU: manley-performance-manley-04-subaru-wrx-sti-ej257-83mm-stroker-99-5mm-std-bore-8-t14-245929
Price: 758.81 USD
Availability: BackOrder

$758.81

On Backorder

Order now to reserve yours — we'll ship as soon as stock arrives. Full refund if we're unable to fulfill.

Fits 2004-2012 Subaru Impreza WRX STi (EJ257). Manley 83mm stroker piston set with rings, 99.5mm bore and 8.5:1 dish. Built for high performance.

Key Features

Fits 2004-2012 Subaru Impreza WRX STi (EJ257).
Manley 83mm stroker pistons with a 99.5mm standard bore.
8.5:1 compression dish design for boosted engines.
Constructed from strong 2618 alloy forgings for durability.
Includes premium chrome moly wrist pins.
Features precise ring lands and grooves for improved ring seal.

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

Secure CheckoutFast Shipping631-982-0042

About this part

Product Details

If you're rebuilding the engine in your 2004-2012 Subaru Impreza WRX STi, specifically with the EJ257 engine, this set of 83mm stroker pistons from Manley Performance is a solid choice. These pistons feature a 99.5mm standard bore and a dish design that results in a compression ratio of 8.5:1, making them suitable for boosted applications where you need to control detonation.

Manley uses domestic 2618 alloy forgings for these pistons, which are known for their strength and ability to handle high cylinder pressures and temperatures. The pistons also come with premium chrome moly wrist pins and have precisely machined ring lands and grooves. This attention to detail helps ensure a good seal with the piston rings, which is crucial for making power and maintaining engine health. The cam and barrel skirt profiles are designed to be effective at generating power while also being gentle on your cylinder walls, reducing wear over time.

These pistons are part of Manley's Platinum Series, which is relied upon by many professional engine builders. They are designed to fit right and perform reliably in demanding builds. Keep in mind that these pistons are not CARB approved and cannot be shipped to California. Always refer to the manufacturer's installation instructions for proper fitment and assembly procedures.