Bull Boost Performance Cylinder 4 Cooling Mod – Subaru EJ20 / EJ25 WRX STI LGT FXT (02–14 WRX / 04–21 STI)

Bull Boost Performance Cylinder 4 Cooling Mod – Subaru EJ20 / EJ25 WRX STI LGT FXT (02–14 WRX / 04–21 STI)

Part Number: 720053572384

Product Description:

Improve engine reliability and cooling efficiency with the Bull Boost Performance Cylinder 4 Cooling Mod, engineered specifically for Subaru EJ-series engines. This upgrade is designed to increase coolant flow to cylinder #4, the hottest and most failure-prone area in EJ platforms.

By improving coolant distribution to the rear of the engine, this modification helps balance overall cylinder temperatures, reducing the risk of detonation and lowering the likelihood of ringland failure. Ideal for both street-driven and performance-built Subaru applications, this is a simple yet highly effective reliability upgrade.

Key Features:

• Premium Bull Boost Performance cooling system upgrade
• Increases coolant flow to cylinder #4 head area
• Helps balance engine-wide coolant temperatures
• Reduces risk of knock and detonation in cylinder #4
• Designed to improve EJ engine reliability under boost
• Simple bolt-on installation design
• Includes all necessary installation components

Fitment:

• Subaru EJ20 / EJ25 engines
• 2002–2014 Subaru WRX
• 2004–2021 Subaru STI
• 2004–2008 Subaru Forester XT
• 2005–2009 Subaru Legacy GT

Included:

• 1x Cylinder 4 Cooling Mod
• 1x T-Fitting
• 2x Clamps

Warranty Disclaimer:

All warranties, claims, and product-related issues must be handled directly through BULL BOOST PERFORMANCE.