Korsh Equal Length 3-Bolt Header & Up-Pipe – Subaru WRX 94–14 / STI 02–21 / Liberty GT 05–09 / Forester XT 04–08

The Korsch Equal Length Header and Up-Pipe system is engineered to deliver measurable performance gains for Australian-delivered Subaru WRX and WRX STI models running EJ-series engines. By utilising a true equal-length 4-2-1 runner configuration with a merged collector, this setup significantly improves exhaust gas balance and turbo efficiency, helping achieve faster turbo spool (approximately 300 RPM sooner) and stronger, more consistent power delivery across the entire rev range.

Constructed entirely from high-quality 304 stainless steel, including cast stainless flanges, this header system is built to withstand the harsh thermal demands of Australian driving conditions—whether on the street, spirited mountain roads, or track use. The 45 mm primary pipe diameter ensures excellent exhaust flow without sacrificing low-RPM response, while the slip-joint expansion section allows for thermal movement during heat cycling, reducing stress and improving long-term reliability. All components are fully TIG welded for maximum strength and precision.

The included 60 mm 3-bolt up-pipe features a cast stainless flange and multi-layer steel gasket to provide a secure, leak-free connection to the turbocharger. All required installation hardware is supplied, including high-quality multi-layer gaskets and copper exhaust nuts that maintain clamping force even under repeated extreme heat cycles.

Please note: Due to the equal-length design, this header will change the exhaust note from the traditional Subaru “boxer rumble” to a smoother, more refined tone.

Key Features

• True equal-length 4-2-1 header design for improved turbo spool and power delivery
• Approximately 300 RPM quicker turbo response compared to factory manifolds
• 304 stainless steel construction with cast stainless flanges
• 45 mm primary piping for optimal exhaust flow
• Slip-joint expansion section to accommodate heat cycling
• Fully TIG welded for strength and durability
• 60 mm 3-bolt stainless steel up-pipe included

What’s Included

• Equal length stainless steel exhaust header
• 3-bolt stainless steel up-pipe
• 3-bolt up-pipe gasket
• Up-pipe to manifold zinc-plated bolts and nuts (x3)
• Up-pipe to turbo threaded studs (x5)
• EGT plug
• Copper flange nuts – manifold to head (x6)
• Manifold to cylinder head gaskets (x2)
• Up-pipe to turbo gasket

Fitment Notes (Australian Vehicles)

• This header removes the factory Subaru boxer rumble
• 2001–2005 WRX requires STI 2.5 L oil pan
• 2006–2007 WRX requires STI oil cooler and STI oil pan
• 2004 Forester XT requires STI oil cooler and STI oil pan
• 2005–2008 Forester XT requires STI oil cooler
• 2005 Liberty GT requires STI oil pan

This system is ideal for Australian Subaru owners chasing improved throttle response, earlier boost, and a smoother exhaust note while maintaining OEM-level fitment and long-term reliability.