Tomei Expreme UnEqual Length Exhaust Manifold GT86, GR86 & BRZTomei Expreme UnEqual Length Exhaust Manifold for Toyota GT86, GR86 & Subaru BRZ Un Equal length 4 1 design for mid range power and to remove the "torque dip" and for the famous "boxer rumble" Optimised pipe lengths and angles Improved flow and efficiency through cat less design Designed for minimum heat transfer to oil pan O2 Sensor port Weight 6. 85kg (Standard manifold is 9. 2kg) Fensport Tip: Ecu will require tuning, we recommend our GT86 & BRZ NA