Koyo Radiator

Part #: HH422674

Overview

The Koyo Radiator for the 1988-1999 BMW 3-Series and M3 is a high-performance cooling solution designed to enhance your vehicle’s thermal management. Crafted with precision, this radiator features a 48mm “HH” Series core with an ultra high fin density, maximizing heat transfer efficiency. It is an ideal upgrade for enthusiasts seeking improved cooling capacity, durability, and reliable performance under demanding conditions. Whether you're restoring a classic or upgrading for enhanced driving confidence, this radiator provides a direct-fit replacement that maintains your vehicle’s original aesthetics while delivering superior cooling support.

Key Features

This radiator combines advanced design and quality materials to ensure optimal performance and longevity. Key features include:

• 48mm high fin density core for maximum heat dissipation
• Precision-engineered to match OEM specifications for a direct fit
• Constructed with durable aluminum for excellent thermal conductivity and corrosion resistance
• Integrated 1/8” NPT female accessory fitting for temperature sensors (includes threaded plug)
• Easy installation with no modifications required
• Designed to support high-performance driving and extended engine life
• Manufactured by Koyo, a trusted name in cooling technology

Construction & Design

The radiator’s core is built with high-density aluminum fins, engineered to maximize surface area for heat transfer. The precision welding and manufacturing process ensure structural integrity and consistent performance. The inclusion of a threaded accessory fitting allows for easy integration of temperature sensors, aiding in monitoring and maintaining optimal engine temperatures.

Installation & Fitment

This radiator is designed as a direct-fit replacement for the stock OEM plastic/aluminum radiator in compatible BMW 3-Series and M3 models from 1988 to 1999. Installation is straightforward, requiring no modifications, making it suitable for both DIY enthusiasts and professional mechanics.

What’s Included

The package includes the high-performance radiator with the integrated accessory fitting and a threaded plug. Additional hardware or accessories are not typically required for installation.