CSF Classic & Small Chassis Audi 5-Cylinder High-Performance All-Aluminum Radiator

With over five decades of specialized experience in radiator manufacturing, CSF stands as a trusted leader in delivering high-quality cooling solutions. The CSF Classic & Small Chassis Audi 5-Cylinder High-Performance All-Aluminum Radiator embodies this legacy, offering exceptional reliability and efficiency tailored specifically for Audi Quattro models including B1, B2, B3, and B4 chassis. Engineered to excel both in everyday driving conditions and demanding motorsport environments, this radiator is an essential upgrade for vehicles requiring enhanced cooling performance, particularly those with high horsepower configurations or engaged in competitive racing.

At the core of this radiator’s superior performance lies CSF’s innovative 2-Row core design integrated with exclusive B-Tube Technology. Unlike conventional oval-shaped “O” tubes, CSF’s uniquely engineered “B” shaped tubes are meticulously formed and seam-brazed, resulting in a structure that is not only stronger but also lighter due to the use of thinner aluminum material. This design innovation increases the heat transfer surface area by approximately 15% compared to traditional tubes, effectively delivering the cooling efficiency of two smaller tubes within the same spatial constraints. The “B-tubes” facilitate dual liquid laminar flow, optimizing coolant movement and heat dissipation.

Complementing the advanced tube design, the radiator incorporates ultra-efficient multi-louvered fins that are precisely aligned to maximize airflow through the core. Each fin’s dimensions and configuration are rigorously calculated and validated through extensive wind-tunnel testing to ensure peak heat rejection efficiency. This meticulous engineering results in a radiator that maintains optimal engine temperatures under intense operating conditions, thereby enhancing engine longevity and performance.

The CSF Audi radiator is designed as a true “Drop-in fit” replacement, requiring no modifications for installation. The inclusion of CNC-machined and welded OE-style mounting brackets guarantees durability and a precise fitment that aligns perfectly with factory specifications. Additionally, inlet and outlet connections are engineered to match original equipment manufacturer (OEM) standards, allowing seamless integration with existing OEM or aftermarket hoses. This thoughtful design ensures that installation is straightforward, minimizing downtime and complexity.

Features

• 2-Row, 42mm Ultra-High-Performance Dual Pass Core for enhanced cooling capacity
• Cooling Tubes utilizing CSF’s proprietary B-Tube Technology for increased strength and efficiency
• 6.5mm Tall Ultra Efficient Fins featuring a Multi-Louvered Design to maximize surface area contact and airflow
• CNC Machined Mounting Brackets and OEM Style Inlet/Outlet connections for precise fitment and compatibility
• Constructed from 100% All Aluminum with TIG-Welded joints ensuring durability and corrosion resistance
• Satin Black Finish providing an OEM+ aesthetic suitable for both street and track applications
• True Plug-and-Play “Drop-in Fit” installation that requires absolutely no modifications
• Individually Leak and Pressure Tested to guarantee reliability and performance consistency
• Modular design allowing use with or without an Auxiliary Radiator for flexible cooling system configurations
• Multiple Fan Shroud Mounting Points compatible with all fan models, including the High Performance RS2 variant
• Multiple overflow pipe locations on the top end tank accommodating different model variations
• Sensor ports sized M22x1.5; early model M20x1.5 sensors may require an adapter
• Backed by a 2-Year Limited Warranty for peace of mind and product assurance

Applications

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.

It is the responsibility of the customer to check with all federal, state local and environmental laws before ordering and installing a product. R44 Performance Limited is not responsible for any fees, fines or costs that a customer may incur as a result of failing to check with federal, state, local or environmental laws before ordering and installing a product.

We get a large number of custom orders and requests everyday, so as a result it is not always possible for us to keep every item in stock at all times in our warehouse. If you require the item urgently please contact our sales team here to check the stock before you make your purchase.

We totally understand if you're not certain a part will be compatible with your car, so we highly recommend contacting us here with your query. Our friendly sales team will then be in touch to confirm if this part is the correct part you are looking for.

All in stock products ship the same day if ordered before 2pm GMT

For out of stock items we will contact you with an estimated wait time if not otherwise specified above.

We offer worldwide shipping on all products. If upon receiving your product you wish to return; we offer a 30-day returns policy. For our in-depth returns information please follow the link. "R44 Returns Policy

All of our products come with a standard warranty of 1-3 years. This is dependant on the type of product however. For more details please see our warranty page here.