GrimmSpeed Equal Length Header – 2022–2025 Subaru WRX (VB) | FA24

Unlock the full performance potential of your 2022–2025 Subaru WRX's FA24 turbocharged flat-four with the GrimmSpeed Equal Length Header. The factory VB WRX uses an unequal length header (ULH) — a design that produces Subaru's iconic burble exhaust note but sacrifices exhaust scavenging efficiency due to uneven exhaust pulse timing reaching the turbocharger. GrimmSpeed's equal length header (ELH) replaces the factory ULH with equal-length primary tubes that deliver even, timed exhaust pulses to the turbocharger — improving exhaust scavenging, reducing turbo lag, and enabling more consistent and higher power output across the RPM range. A significant performance upgrade for any serious VB WRX build.

Key Features

• Equal Length Primary Tubes: Equal-length primary tubes deliver even, timed exhaust pulses to the FA24's turbocharger — improving exhaust scavenging efficiency compared to the factory unequal length header
• Reduced Turbo Lag: More consistent and efficient exhaust pulse delivery to the turbocharger reduces turbo lag for improved throttle response and power delivery
• Improved Power Output: Enhanced exhaust scavenging and more efficient turbocharger spool enables higher and more consistent power output across the RPM range on a supporting tune
• Replaces Factory ULH: Direct replacement for the factory VB WRX unequal length header — engineered specifically for the FA24 engine and VB chassis packaging
• Sound Character Change: Equal length headers eliminate the uneven exhaust pulse timing that produces Subaru's iconic burble — the exhaust note will be smoother and more conventional compared to the factory ULH sound
• GrimmSpeed Quality: Manufactured by GrimmSpeed — a trusted name in Subaru performance parts with a proven track record on the WRX and STI platforms

Specifications

• Type: Equal Length Header (ELH)
• Replaces: Factory Unequal Length Header (ULH)
• Engine: Subaru FA24 Turbocharged Flat-Four
• Fitment: 2022–2025 Subaru WRX (VB)
• Part Number: 113401

Note: An ECU tune is required after installation — running an equal length header on a stock tune will result in suboptimal performance and may trigger fault codes. This header will change the exhaust sound character of the WRX — the iconic Subaru burble associated with the factory ULH will be reduced or eliminated. A downpipe upgrade is recommended to complement the ELH for maximum performance gains. Professional installation by an experienced Subaru performance shop is strongly recommended.