T304 Stainless Steel UEL 4‑1 Exhaust Header Manifold With 3 O2 Sensor Bungs For Toyota GT86 Subaru BRZ FA20 2.0L 2012‑2021

DESCRIPTION

This unequal‑length UEL 4‑1 exhaust header manifold is purpose‑built for Toyota GT86 / Subaru BRZ FA20 2.0L boxer engine. It comes with 3 pre‑welded O2 sensor bungs for professional ECU tuning, delivers the iconic deep boxer rumble exhaust tone. Optimized mandrel‑bent runners reduce exhaust backpressure, smooth exhaust gas velocity and resolve the well‑known factory 3000‑4500 RPM torque dip for linear power output. Made of heavy‑gauge T304 stainless steel with full TIG welding and CNC machined thick flanges, it resists cracking under high‑temperature street and track driving. Direct bolt‑on fit, no cutting or extra welding required for installation.

VEHICLE FITMENT

KEY FEATURES

• 3 Pre‑Welded O2 Sensor Bungs (M18×1.5): Compared with standard 2‑bung headers, extra third bung supports wideband AFR sensor installation for professional ECU tuning. Blanking plug is included for unused port, no drilling or on‑site welding needed.
• Unequal‑Length UEL 4‑1 Runner Design: Optimized unequal‑length runners redirect boxer‑engine exhaust pulses, producing authentic deep aggressive boxer rumble sound signature.
• High‑Flow Runner Geometry: Mandrel‑bent tubing minimizes internal turbulence, lowers exhaust backpressure, smooths gas velocity and improves linear power delivery, resolves factory 3000‑4500 RPM torque dip.
• Heavy‑Duty T304 Stainless Steel Build: Premium mandrel‑bent T304 stainless steel material, lighter than stock cast iron manifold, anti‑corrosion and high‑temperature resistant.
• CNC‑Machined Thick Flanges: Precision CNC machined thick flanges keep flat sealing surface under repeated thermal cycles, effectively prevent exhaust leakage.
• Full TIG Argon‑Arc Welding: Fully hand TIG welded construction, anti‑crack performance for street and aggressive track usage.
• Direct Bolt‑On Installation: Matches OEM mounting points, flange positions and mounting lugs, bolt‑on replacement without cutting or modification.

TECH SPECIFICATIONS

• Main Material: T304 stainless steel
• Surface Treatment: Mirror polished
• Welding Process: Full TIG argon‑arc welding
• Flange: CNC machined thick steel flange
• Sensor Bungs: 3 x M18×1.5 O2 sensor ports, with blanking plug
• Structure: UEL unequal‑length 4‑1 merge collector
• Engine: FA20 2.0L Boxer four‑cylinder
• Chassis: ZN6 / ZC6
• Fitment Year: 2012‑2021
• Body Type: Car (Coupe)

WHAT'S IN THE BOX

• 1 x UEL 4‑1 Exhaust Header Manifold
• Blanking plug for unused sensor port
• Full Set OEM Matching Installation Gaskets & Hardware Kit