Koyo HH 48MM Racing Radiator - BMW E46 M3 (2001-2006)

HH422675 - Koyo HH 48MM Racing Radiator - BMW E46 M3 (2001-2006)

Upgrade the cooling performance of your 2001–2006 BMW E46 M3 with the Koyorad HH Series All-Aluminum Performance Radiator. Designed as a direct replacement for the factory plastic/aluminum radiator, this high-performance cooling solution delivers increased coolant capacity, improved airflow, and more efficient coolant circulation while maintaining an OEM-style fit.

At the heart of the radiator is Koyorad’s HH Series high-density, dual-row 48mm aluminum core, engineered to provide significantly greater cooling capability than the factory radiator. Whether your E46 M3 is a street car, track build, or modified performance setup, the increased cooling capacity helps keep temperatures under control when the S54 is being pushed hard.

Precision-engineered specifically for the E46 M3 chassis, the radiator installs using the factory mounting locations and is designed to work with the OEM fan shroud for a straightforward installation. Unlike universal-fit alternatives, the tanks and core are purpose-built for this application to provide proper fitment without unnecessary modification.

Finished in polished aluminum and constructed with Koyorad’s high-quality welding and brazing processes, this radiator combines performance, durability, and a clean appearance worthy of the E46 M3.

Features

• Fits 2001–2006 BMW E46 M3

• Direct replacement for the factory OEM radiator

• HH Series high-density dual-row 48mm core

• Increased coolant capacity for improved cooling performance

• Provides approximately 20–30% greater cooling capacity than standard radiators

• Designed for high-revving and high-performance engines

• Ideal for street, track, and modified applications

• Suitable for turbocharged, supercharged, and nitrous-equipped vehicles

• Constructed from high-quality aluminum

• Precision welded aluminum tanks

• NOCOLOK-brazed core construction with no epoxy

• Application-specific core and tank design—no universal-fit components

• Compatible with the factory fan shroud

• Polished aluminum finish

• Engineered for OEM-style fitment and straightforward installation

Vehicle Fitment

BMW M3 (E46)
2001–2006

A great cooling upgrade for E46 M3 owners looking to replace the aging factory radiator while adding increased cooling capacity, durability, and performance.