The HKS Equal Length Header (Exhaust Manifold) for the Subaru EJ25 motor works on the 04-14 Impreza WRX STI and the new 15+ WRX STI. It replaces the OEM header for better flow and performance using a 4-1 setup to improve low range and high range performance (mid-range is at OEM level) with all things the same. Increase exhaust flow with the improved spool, providing a win-win situation. This is a great product for those looking to push the power from their OEM turbo setup or those using OEM style 2-bolt flanged pipes. This is also a great addition to lower EGT. This item includes all necessary hardware for an easy installation.
**Going from unequal to equal length will change exhaust note from rumble to a higher pitch**
Please Note
- Main/Bypass Pipe size: 42.7, Main/Bypass Pipe thickness: 2, For WRX STI A-Line 4door SUH409
- NOT CARB Legal! NO CALIFORNIA SALE!
- OFF-ROAD ONLY!
Applications
- Subaru Impreza WRX STI (2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014)
- Subaru WRX STI (2015, 2016, 2017, 2018, 2019, 2020, 2021)
Features
- 4-1 Exhaust Manifold (almost 4-2-1 setup)
- Quad 42.7mm to dual to single 52mm piping
- Increasing Low/High range power (mid-range same as OEM)
- Can be used with the OEM Oil Pan
- Made of SUH409 Steel
- Made in Japan
Extended Information
- Type: 4-1 Exhaust Manifold
- Catalyzer: none
- Material: SUH409
- Diameter: 42.7 - 52 [mm]
- Chassis: GDB / GVB / GRB / VAB
- Engine: EJ25
- Notes: All hardware included
- Warranty: HKS Manufactures Warranty
Customer Reviews
Customer Questions
RETURN & CANCELATION POLICY | INTERNATIONAL DUTIES AND TAXES
In stock, non special order items can be returned within 30 days of the product arriving to your house or place of work.
Returns will NOT be accepted on Clearance Items, Final Sales, Special Orders, Opened, Installed, Incomplete, or Otherwise Used Products. In order to initiate a return, an RMA number must be requested and approved via e-mail.
All returns will be subject to a 20% restocking fee minus complete shipping cost (roundtrip).
Any processed orders that have not shipped will incur a 6% cancelation refund fee unless the product was not available to ship within a timely manner. No fee will be incurred if used as store credit.
For complete details on our return policy, please see our Help and FAQ link under HELPFUL INFO.
INTERNATIONAL DUTIES AND TAXES
All international orders outside of the USA are subject to duties and taxes per your countries jurisdiction and determined by customs.
Kami Speed serves the right to ship using an alternative method if we see it fit, in order to expedite shipping and reduce your rate depending on product value.

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