CSF MK3 Ford Focus RS High-Performance All-Aluminum Radiator

The Ford Focus RS MK3 stands as a testament to engineering excellence, delivering remarkable performance straight from the factory. Nevertheless, when subjected to increased power demands or rigorous driving conditions such as track use or elevated ambient temperatures, the standard cooling system may encounter limitations. Addressing these challenges, the CSF MK3 Ford Focus RS High-Performance All-Aluminum Radiator offers an advanced solution engineered to maintain optimal coolant temperatures, thereby preserving engine integrity and performance.

With a legacy spanning over five decades in radiator manufacturing, CSF brings unparalleled expertise to the development of this high-performance cooling component. The radiator is meticulously designed to excel in both street and competitive motorsport environments, making it an indispensable upgrade for high horsepower builds and race-prepared vehicles alike. Central to its superior performance is the 2-Row core construction featuring CSF's proprietary B-Tube Technology. Unlike conventional oval “O” shaped tubes, the B-Tubes are engineered with a unique “B” profile, which is seam-brazed to enhance structural integrity. This innovative design allows the use of thinner, lighter aluminum material without compromising strength, resulting in approximately 15% greater heat transfer surface area compared to traditional tubes. The increased surface area facilitates dual liquid laminar flow, significantly improving thermal efficiency within the same spatial constraints.

Complementing the advanced tubing, the radiator incorporates ultra-efficient multi-louvered fins precisely aligned to maximize airflow through the core. Each fin specification is carefully calibrated and validated through rigorous wind tunnel testing to ensure optimal heat rejection performance. This attention to detail guarantees that the radiator delivers consistent and reliable cooling under demanding conditions.

Installation is straightforward due to the radiator’s true “drop-in fit” design, which requires no modifications to the vehicle. All mounting brackets are CNC machined and welded to OEM standards, ensuring durability and precise fitment. The inlet and outlet connections are engineered to match original equipment specifications, allowing seamless integration with existing OEM or aftermarket hoses. This facilitates a hassle-free upgrade experience while maintaining system integrity.

Product Details

Design & Engineering

CSF collaborated with industry-leading EcoBoost specialists to address the prevalent issue of elevated coolant temperatures reported by Focus RS owners, particularly those operating higher power racing engines. The resulting radiator upgrade is optimized for both performance and fitment, now accessible globally through CSF’s extensive dealer and distributor network.

While engineered for high-performance racing applications, this radiator also benefits any Focus RS owner. Even moderate power enhancements or aggressive driving can impose additional thermal stress on the factory cooling system. The CSF radiator serves as the ultimate solution to maintain engine temperature within safe operating limits, enhancing reliability and longevity.

CSF vs OEM

The original equipment (OE) radiator supplied by Ford features a plastic tank and a single-row aluminum core. While adequate for standard driving conditions, this configuration is suboptimal for vehicles subjected to increased power output or demanding driving scenarios. Turbocharged engines, such as the 2.3L EcoBoost in the Focus RS, inherently generate significant heat, necessitating superior cooling solutions to safeguard engine components and maintain performance consistency.

The CSF radiator’s 42mm thick 2-Row aluminum core represents a substantial advancement over the factory 36mm single-row core. The increased thickness, dual cooling rows, and augmented fluid capacity collectively enhance the system’s ability to absorb and dissipate heat efficiently. CSF’s Exclusive B-Tube Technology further elevates heat transfer efficiency by approximately 15% compared to conventional oval welded tubes. Additionally, the multi-louvered fin design maximizes airflow and thermal exchange within the core.

Constructed from 100% TIG-welded aluminum, the radiator exhibits superior strength and durability relative to OEM units that utilize plastic tanks and crimped gaskets. This robust construction ensures long-term reliability and resistance to thermal cycling and mechanical stress, instilling confidence in the radiator’s performance over extended service life.

Triple Pass Advantage

A defining feature of the CSF radiator is its Triple Pass flow configuration. This internal routing compels the coolant to traverse the radiator core three times before exiting, significantly enhancing heat dissipation

Unless explicitly stated otherwise, all products sold by R44 Performance Limited are designated RACE ONLY and are solely for competition or off-road use limited to racing formally sanctioned by a recognized racing organization. Any other use, including recreational off-road use, may violate local, state, and Federal laws. R44 Performance Limited does not implicitly or explicitly confirm the legality of using any products it sells on public roads; that is entirely the responsibility of the consumer.

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