Manley 04+ Subaru WRX/STi (EJ257) 99.75mm Bore 1.2mm x 1.2mm x 2.0mm +.25mm Oversized Ring Set

SKU: 46997-4 | UPC: 807298041155

Manley 2004+ Subaru WRX/STI (EJ257) 99.75mm Bore 1.2mm x 1.2mm x 2.0mm +.25mm Oversized Ring Set

This Manley piston ring set fits 2004-2021 Subaru WRX/STI models equipped with EJ257 turbo engines after boring cylinders to 99.75mm. The 1.2mm x 1.2mm x 2.0mm configuration ensures precise cylinder sealing and effective oil control in engines handling elevated boost levels and RPM. Engine builders rely on these rings for rebuilt turbo setups that withstand intense performance demands.

Key Features

• Top Ring: High tensile strength steel with hard chrome face resists scuffing and holds seal integrity under high cylinder pressures
• Second Ring: Reverse bevel nitrided ductile iron promotes heat transfer and cuts friction for smoother operation
• Oil Ring: Three-piece design with steel top rail expander and flex-vent side rails meters oil consistently across all conditions
• Oversize Bore: 99.75mm (+.25mm) dimension matches overbored EJ257 blocks and coordinates with Manley pistons for exact fit
• Engine Specific: Designed exclusively for Subaru EJ257 turbo engines with optimized tension and gap settings for reliability

Product Notes

• Rings require end gap verification and filing to engine builder specifications for best results
• Best paired with forged pistons in high compression or boosted configurations
• Packaged to arrive undamaged and ready for inspection

Installation Notes

• Professional installation recommended.
• Set ring end gaps to 0.004-0.005 inch per inch of bore for top ring and follow specs for others
• Works with OEM heads gaskets and aftermarket pistons at 99.75mm bore diameter

This Part Fits

Year	Make	Model	Submodel
2004-2012	Subaru	Impreza	WRX STI
2004-2007	Subaru	Impreza	WRX STI hatchback/sedan
2007	Subaru	Impreza	WRX STI Limited
2008-2014	Subaru	Impreza	WRX STI hatchback
2010	Subaru	Impreza	WRX STI Special Edition
2011-2012	Subaru	Impreza	WRX STI Limited
2013-2014	Subaru	Impreza	WRX STI
2015-2021	Subaru	WRX	STI

Why Choose Manley?

• Over 30 years crafting engine parts for motorsports
• Built in USA facilities with tight tolerances for reliability
• Used in championship winning Subaru race engines

Frequently Asked Questions

• Q: Does this fit all EJ257 engines in 2004+ STI models?
  A: Yes for 2004-2021 Impreza WRX STI variants with EJ257 when cylinders are bored to 99.75mm
• Q: What ring materials are used?
  A: Top ring is chrome faced steel second is nitrided ductile iron oil ring uses steel and flex vent components
• Q: What warranty applies and install tips?
  A: Limited manufacturer defect warranty always gap rings precisely and torque to spec during assembly

Shipping & Handling

• Method: UPS Ground
• Availability: In stock – ships same or next business day
• Packaging: Secure box 5 x 5 x 1 inches
• Weight: 0.65 lbs