Torque Solution TS-SU-636 R35 GTR COP Adapter Kit 01-21 Subaru EJ20 EJ25 DIY

Vehicle Fitment

• 2001-2007 Subaru Impreza WRX (EJ20 2.0L / EJ25 2.5L Turbo)
• 2008-2014 Subaru Impreza WRX (EJ255 2.5L Turbo)
• 2001-2007 Subaru WRX STI (EJ20 2.0L / EJ25 2.5L Turbo)
• 2008-2014 Subaru WRX STI (EJ257 2.5L Turbo)
• 2015-2021 Subaru WRX STI (VAB, EJ257 2.5L Turbo)
• 2003-2013 Subaru Forester XT (EJ255 2.5L Turbo)
• 2004-2009 Subaru Legacy GT (EJ20/EJ25 Turbo)

Fitment Notes

• DIY / Adapter Kit Only - Hitachi IGC0079 coil packs are NOT included. This listing (TS-SU-636) contains only the adapter hardware, harnesses, stalks, and boots. You must source compatible Genuine Hitachi R35 GTR ignition coils separately. For the complete kit with coils included, see TS-SU-636-K.
• Compatible with all 2001-2021 Subaru EJ20 and EJ25 engines - fits both driver-side and passenger-side cylinder banks via the included side-specific billet adapter spacers
• Must be used exclusively with Genuine Hitachi ignition coils for the Nissan R35 GTR. Compatible Hitachi coil part numbers: IGC0079 (North America), 22448-JF00B (OEM Nissan/Hanshin), 9X01 2410N (Hitachi Europe), HEX EXA 2410N (Hitachi ASEAN), U18N02 (Hitachi Japan). Aftermarket or counterfeit R35 coils are not recommended and may not seat or perform correctly with this kit.
• Dwell settings must be adjusted per the Torque Solution installation guide after installation - failure to set correct dwell may result in misfires or coil damage
• Not for sale in California

Features

• Allows installation of Genuine Hitachi R35 GTR ignition coils (as used in the VR38DETT-powered Nissan GT-R) onto Subaru EJ20 and EJ25 engines - providing a proven, high-energy coil upgrade without custom fabrication
• Completely plug-and-play - CNC billet aluminum adapter spacers, custom Teflon stalk spacers, OEM-style coil boots, and plug-and-play wire harness adapters allow direct bolt-on installation without cutting or splicing factory wiring
• R35 GTR Hitachi coils produce nearly double the spark energy of OEM Subaru EJ coil packs - directly addressing the EJ platform's well-documented spark blowout issue under sustained high boost
• Enables running significantly larger spark plug gaps than the OEM coils allow, which improves combustion efficiency, throttle response, idle quality, and acceleration on modified EJ builds
• Allows running substantially more boost over OEM coil limits - critical for high-power EJ builds where spark blowout under boost is a primary ignition failure mode
• Side-specific CNC billet aluminum adapter spacers (driver side and passenger side) mount the differently-sized R35 coil bodies correctly to each cylinder bank
• Custom CNC Teflon stalk spacers position the R35 coil pack at the correct height above the spark plug, and the included OEM-style rubber coil boots seal around the plug well
• The Hitachi coil pack retains its original internal coil spring and fuse for the best possible spark contact and energy transfer
• Plug-and-play adapter harnesses connect the EJ-series ignition wiring connector directly to the R35 GTR coil pack connector - no modifications to the factory harness
• All stainless steel hardware included - corrosion-resistant and properly torqued mounting for both the billet adapters and coil packs
• Limited Lifetime Warranty

Specifications

• Part Number: TS-SU-636
• Brand: Torque Solution
• Product Type: R35 GTR Coil On Plug (COP) Adapter Kit - DIY (Coils Not Included)
• Compatible Coils: Genuine Hitachi R35 GTR Ignition Coils (IGC0079 / 22448-JF00B / 9X01 2410N / HEX EXA 2410N / U18N02)
• Adapter Material: CNC Billet Aluminum (side-specific)
• Stalk Material: CNC Teflon
• Boot Type: OEM-Style Rubber Coil Boot
• Harness: Plug-and-Play (no wiring modification required)
• Hardware: All Stainless Steel
• Application: 2001-2021 Subaru EJ20 / EJ25 Engines (WRX, WRX STI, Forester XT, Legacy GT)
• California Legal: No
• Warranty: Limited Lifetime

Included Components

• 2x CNC Billet Aluminum Driver Side Adapter Spacer
• 2x CNC Billet Aluminum Passenger Side Adapter Spacer
• 4x CNC Teflon Stalk Spacer
• 4x OEM-Style Rubber Coil Stalk Boot
• 4x Plug-and-Play Wire Harness Adapter
• 4x M8-1.25 x 30mm Stainless Steel Socket Cap Bolt (mounts billet adapters to engine)
• 4x M6-1.0 x 35mm Stainless Steel Button Head Bolt (mounts coil packs to billet spacers)
• 4x M6 Stainless Steel Flat Washer

Product Description

The Torque Solution TS-SU-636 is a coil-on-plug (COP) adapter kit that enables the installation of Genuine Hitachi R35 Nissan GTR ignition coils onto Subaru EJ20 and EJ25 engines - covering all WRX, WRX STI, Forester XT, and Legacy GT applications using these engines from 2001 through 2021. Spark blowout under boost is one of the most well-documented power-limiting issues on the EJ platform: the OEM Subaru coil packs, while adequate for stock boost levels, are insufficient for the spark energy demands of modified high-boost builds. Under sustained high-boost conditions, the OEM coils struggle to maintain a consistent arc across a large plug gap, resulting in misfires, rough power delivery, and a hard ceiling on both boost and spark plug gap size. The R35 GTR Hitachi coils - which power the twin-turbocharged VR38DETT in the Nissan GT-R - produce nearly double the spark energy of the factory Subaru units and are widely regarded as the benchmark coil upgrade for the EJ platform.

This is the DIY adapter-only version (TS-SU-636) - the Hitachi coil packs themselves are not included. Builders who already own compatible Genuine Hitachi R35 coils (IGC0079 / 22448-JF00B / regional equivalents) can use this kit alone. Those who need the complete solution with coils should see TS-SU-636-K. The adapter kit is fully plug-and-play: two pairs of side-specific CNC billet aluminum adapter spacers bolt directly to the engine's coil mounting points (driver and passenger sides have different geometries and are not interchangeable), while four custom CNC Teflon stalk spacers and OEM-style rubber coil boots position and seal each R35 coil pack correctly over the spark plug well. Four plug-and-play wire harness adapters connect the EJ-series factory connectors to the R35 coil pack connectors without any wiring modification. The R35 coil packs retain their OEM internal spring and fuse throughout, preserving the coil's internal contact integrity.

After installation, dwell settings must be adjusted per the Torque Solution installation guide - this is a required configuration step and should not be skipped. The benefits of a correctly installed and tuned R35 COP conversion include smoother idle, sharper throttle response, improved acceleration under load, the ability to run larger spark plug gaps than OEM allows, and critically - the ability to sustain boost levels that would cause spark blowout on stock coils. Backed by Torque Solution's Limited Lifetime Warranty. Not for sale in California.