The CSF Universal Large Single-Pass High-Performance Oil Cooler (8371) is a premium cooling solution engineered for demanding street, track, and custom performance applications. Featuring CSF's proprietary Aero-Flow bar/plate core, TIG-welded end tanks, large M22 x 1.5 fluid connections, and a durable satin black finish, this universal cooler is designed to provide efficient heat transfer, excellent fluid flow, and exceptional structural durability.

Developed as part of CSF's high-performance cooling lineup, the 8371 combines advanced cooling technology with a rugged construction designed to withstand demanding operating environments. Unlike conventional stacked-plate oil coolers, the CSF Aero-Flow bar/plate design emphasizes efficient airflow, fluid flow, and resistance to vibration and physical damage.

One of the standout features of the CSF 8371 is its large single-pass cooling configuration. The vertically oriented inlet and outlet connections provide a traditional oil cooler layout, making it suitable for a wide variety of custom installations. This arrangement can simplify fluid line routing in applications where both connections are best positioned along the same side of the cooler.

The CSF 8371 features a substantial cooling core measuring 9.25 inches long, 9.33 inches high, and 2.16 inches wide, providing a large surface area for heat dissipation. Overall dimensions, including the fitting bosses, measure 12 inches long, 9.85 inches high, and 2.36 inches wide.

Designed for versatility, the 8371 can be utilized for several different fluid-cooling applications, including engine oil, transmission fluid, power steering fluid, differential oil, and compatible liquid-to-liquid heat exchanger systems. This flexibility makes it an excellent option for performance enthusiasts, professional fabricators, and custom vehicle builders.

The cooler incorporates M22 x 1.5 threaded inlet and outlet connections, offering compatibility with a wide range of aftermarket adapter fittings. These connections feature an internally radiused design to promote fluid flow and can accommodate appropriately configured fittings up to -16AN.

Another important feature is the inclusion of four 1/8-inch NPT auxiliary ports, with two ports located on each end tank. These additional ports can be utilized for temperature sensors, bleeding provisions, or other compatible fluid-system accessories, depending on the installation requirements.

For installation flexibility, CSF incorporates triangular flush-mounting provisions with M8 x 1.25 threaded holes on the top and bottom of the cooler. These mounting points allow fabricators to design secure mounting brackets for a variety of vehicle configurations.

The cooler's TIG-welded end tanks provide additional structural strength compared to conventional brazed assemblies, helping improve durability under demanding operating conditions. Its satin black finish also provides protection against corrosion and debris while delivering a clean, professional appearance.

With a 1.5-liter (1.6-quart) fluid capacity and a pressure-tested construction rated at 120 psi during manufacturer testing, the CSF 8371 offers a substantial cooling solution for custom performance applications.

Whether upgrading the engine oil cooling system on a turbocharged Honda or Acura, improving transmission fluid temperature management, or building a custom motorsport cooling system, the CSF 8371 delivers advanced cooling technology and the durability expected from CSF's performance products.

Features

• CSF High-Performance Cooling Technology: Engineered for demanding aftermarket and custom cooling applications.

• Large Single-Pass Design: Provides a traditional cooling configuration with vertically oriented inlet and outlet connections.

• Proprietary Aero-Flow Bar/Plate Core: Designed to optimize airflow and fluid flow while maintaining excellent structural durability.

• High-Efficiency Cooling Construction: Provides substantial heat-transfer surface area for demanding fluid-cooling applications.

• TIG-Welded End Tanks: Offers increased structural strength and resistance to leakage compared to conventional brazed construction.

• Large Cooling Core: Features a 9.25-inch long, 9.33-inch high, and 2.16-inch wide core.

• Compact Overall Packaging: Measures 12 inches long, 9.85 inches high, and 2.36 inches wide, including fitting bosses.

• M22 x 1.5 Inlet and Outlet Connections: Provides compatibility with a wide selection of aftermarket fluid fittings.

• Up to -16AN Fitting Compatibility: Large threaded connections support appropriately configured high-flow AN adapter fittings.

• Internally Radiused Fluid Connections: Designed to promote efficient fluid flow through the cooler.

• Four Auxiliary 1/8-Inch NPT Ports: Provides additional connection options for temperature sensors and bleeding provisions.

• 1.5-Liter Fluid Capacity: Offers approximately 1.6 quarts of internal fluid volume.

• Triangular Flush-Mounting Provisions: Provides multiple attachment points for custom mounting bracket fabrication.

• M8 x 1.25 Threaded Mounting Holes: Allows the use of commonly available metric mounting hardware.

• Multiple Mounting Orientations: Can be positioned horizontally or vertically depending on the application.

• Satin Black Protective Finish: Helps protect against corrosion and debris while providing a professional appearance.

• Rugged Bar/Plate Construction: Designed to withstand vibration and demanding installation environments.

• Pressure Tested at 120 PSI: Manufacturer-tested to verify cooling assembly integrity.

• Universal Application: Suitable for a wide range of custom fluid-cooling installations.

• Multi-Fluid Cooling Capability: Can be used for engine oil, transmission oil, differential oil, power steering fluid, and compatible coolant applications.

• Professional Fabrication Compatibility: Designed for custom mounting, plumbing, and fluid-system integration.

• Two-Year Limited Manufacturer Warranty: Backed by CSF's applicable warranty coverage.

Popular Performance Applications

• Honda Civic K-Series Performance Builds: Suitable for custom engine oil cooling systems on modified K20 and K24 applications.

• Acura Integra Performance Builds: Provides a high-capacity cooling option for custom engine oil and transmission cooling configurations.

• Honda Civic Type R Custom Cooling Systems: Can be incorporated into fabricated cooling systems where space, fluid compatibility, and plumbing requirements permit.

• Acura RSX Performance Builds: Suitable for custom external oil cooling systems on high-performance K-Series engines.

• Honda S2000 Performance Builds: Provides an oil cooling option for properly engineered custom installations.

• Honda Accord Performance Builds: Suitable for modified engine and transmission cooling systems requiring additional heat management.

• K20 and K24 Engine Swaps: Can be incorporated into custom oil cooling systems for naturally aspirated and turbocharged K-Series engines.

• B16, B18, and B20 Performance Builds: Suitable for custom external oil cooling systems on modified B-Series engines.

• Turbocharged Honda and Acura Applications: Provides additional heat-management capacity for compatible high-output engine configurations.

• High-Performance Transmission Cooling: Can be used in custom transmission fluid cooling systems with appropriate plumbing and fluid compatibility.

• Differential Cooling Systems: Suitable for custom differential oil cooling applications requiring a large external heat exchanger.

• Power Steering Cooling Systems: Can be integrated into properly configured hydraulic power steering cooling circuits.

• Custom Motorsport Applications: Provides a rugged cooling solution for professionally engineered competition vehicle systems.

• Custom Heat Exchanger Applications: May be utilized in compatible liquid cooling systems where the cooler's materials, pressure requirements, and fluid compatibility are appropriate.

Important: These are potential custom applications rather than confirmed direct-fit vehicle applications. The CSF 8371 requires application-specific mounting, plumbing, and clearance verification.

Additional Information

• Manufacturer: CSF
• Part Number: 8371
• Product Type: Universal High-Performance Oil Cooler
• Cooling Configuration: Large Single-Pass
• Core Construction: High-Efficiency Aero-Flow Bar/Plate
• End Tank Construction: TIG-Welded
• Finish: Satin Black
• Inlet Connection: M22 x 1.5
• Outlet Connection: M22 x 1.5
• Maximum Adapter Size Supported by Port Design: Up to -16AN
• Auxiliary Connections: Four 1/8-Inch NPT Ports, Two Per End Tank
• Mounting Provisions: Triangular Flush-Mounting Holes
• Mounting Thread Size: M8 x 1.25
• Core Length: 9.25 Inches (235 mm)
• Core Height: 9.33 Inches (237 mm)
• Core Width: 2.16 Inches (55 mm)
• Overall Length: 12 Inches (305 mm)
• Overall Height: 9.85 Inches (250 mm)
• Overall Width: 2.36 Inches (60 mm)
• Fluid Capacity: 1.5 Liters (Approximately 1.6 Quarts)
• Manufacturer Pressure Test: 120 PSI
• Vehicle Fitment: Universal / Custom Fit
• Installation Type: Custom Mounting and Plumbing Required
• Manufacturer Warranty: 2-Year Limited Warranty
• UPC: 710353083710

Universal Fitment Information

The CSF 8371 is a universal cooling component rather than a vehicle-specific direct-fit replacement.

Before ordering, verify the following:

• Overall Dimensions: 12 inches long, 9.85 inches high, and 2.36 inches wide.

• Cooling Core Dimensions: 9.25 inches long, 9.33 inches high, and 2.16 inches wide.

• Fluid Connection Size: M22 x 1.5 threaded inlet and outlet ports.

• Auxiliary Port Requirements: Four 1/8-inch NPT ports must be appropriately utilized or sealed.

• Mounting Hardware: M8 x 1.25 threaded mounting provisions.

• Fluid Compatibility: Confirm suitability for the specific oil, hydraulic fluid, or coolant used in the application.

• Available Airflow: Position the cooler where sufficient airflow is available for effective heat transfer.

• Fluid Line Routing: Ensure adequate clearance for hoses, fittings, and surrounding components.

• System Pressure Requirements: Verify that the cooler is suitable for the intended system's operating conditions.

• Additional Fluid Capacity: Account for the cooler's approximately 1.5-liter internal volume when filling the system.

Aero-Flow Bar/Plate Core Technology

The CSF 8371 utilizes the company's proprietary Aero-Flow bar/plate cooling core.

This design is engineered to provide efficient heat transfer while maintaining a durable structure capable of withstanding vibration and physical stress.

Compared with conventional stacked-plate coolers, the CSF bar/plate construction offers a rugged design intended for demanding automotive applications.

The Aero-Flow core also emphasizes efficient fluid movement and airflow through the cooling assembly.

This combination makes the 8371 particularly attractive for applications where both cooling performance and structural durability are important.

TIG-Welded End Tank Construction

The CSF 8371 features TIG-welded end tanks rather than relying exclusively on conventional brazed end-tank construction.

This design provides a strong connection between the cooler core and fluid connections.

TIG-welded construction helps improve resistance to vibration and mechanical stress, making the cooler suitable for demanding custom installations.

Proper mounting and fluid line support remain essential to prevent excessive stress on the cooler and its threaded connections.

M22 x 1.5 and -16AN Connection Compatibility

The cooler features M22 x 1.5 threaded inlet and outlet connections.

These large-diameter ports allow the use of compatible adapter fittings, including appropriately configured fittings up to -16AN.

The connections incorporate an internal radius designed to support efficient fluid movement.

Important: The cooler does not have native -16AN male threads. Connecting -16AN hoses requires compatible M22 x 1.5-to-AN adapter fittings.

Always verify fitting thread engagement, sealing design, hose size, and system pressure requirements before installation.

Auxiliary Temperature Sensor and Bleeding Ports

The CSF 8371 includes four auxiliary 1/8-inch NPT ports, with two located on each end tank.

These ports provide flexibility for adding compatible temperature sensors or bleeding provisions.

For engine oil cooling applications, temperature sensors may help monitor cooling performance and fluid operating conditions.

For compatible coolant or hydraulic applications, auxiliary ports may also provide convenient bleeding locations when appropriately positioned.

Any unused ports must be sealed using compatible threaded plugs and the correct sealing method.

Mounting Flexibility

The CSF 8371 incorporates triangular flush-mounting provisions with M8 x 1.25 threaded holes.

These mounting points allow fabricators to design application-specific brackets.

The cooler may be mounted in different orientations depending on available space, airflow, and fluid routing.

CSF notes that vertical installation with the inlet and outlet connections facing upward or downward will be common for many universal applications.

Regardless of mounting orientation, the installation should provide secure support, adequate airflow, and appropriate fluid bleeding provisions.

Fluid Cooling Applications

The CSF 8371 can be used in several different types of cooling systems.

Engine Oil Cooling: Helps dissipate heat from engine oil in appropriately configured external oil cooling systems.

Transmission Oil Cooling: Can provide additional heat management for compatible automatic or other transmission fluid circuits.

Differential Oil Cooling: Suitable for custom differential cooling systems equipped with the required pump, plumbing, and temperature-management components.

Power Steering Cooling: May be incorporated into compatible hydraulic power steering systems.

Coolant Heat Exchanger Applications: Can be used in suitable water/coolant heat exchanger configurations where the system's operating conditions are compatible.

The cooler must be properly sized and integrated for the intended application. A universal cooler should not be assumed to work with every fluid or cooling system without verification.

Pressure Testing and System Requirements

CSF pressure-tests the 8371 at 120 PSI during manufacturing.

This test verifies the integrity of the cooling assembly but should not be interpreted as a universal maximum continuous operating pressure rating for every application.

Before installation, confirm that the cooler, fittings, hoses, and related components are appropriate for the operating pressures and temperatures of the intended system.

Cooling Performance Information

The CSF 8371 is designed to improve heat dissipation when properly integrated into a suitable fluid-cooling system.

Actual temperature reductions depend on airflow, fluid flow, ambient temperature, heat load, mounting location, and the remaining cooling system.

Specific temperature reductions or horsepower gains are not guaranteed.

For engine oil applications, a properly selected thermostat or temperature-control system may be necessary to prevent excessive oil cooling during normal street operation.

Common Reasons for Replacement

• Elevated Engine Oil Temperatures: Provides additional cooling capacity for properly configured external oil cooling systems.

• Turbocharged Engine Builds: Helps manage increased thermal demands associated with high-output performance applications.

• Track and Competition Use: Offers a rugged cooling component for demanding custom vehicle systems.

• Insufficient Factory Oil Cooling: Provides an option for upgrading cooling capacity where the factory system is inadequate.

• Damaged Oil Coolers: Replaces leaking, cracked, or physically damaged cooling components.

• Custom Cooling System Fabrication: Provides a versatile heat exchanger for custom engine, transmission, and differential cooling projects.

• High-Performance Transmission Builds: Can be incorporated into systems requiring additional transmission fluid heat management.

• Differential Temperature Management: Provides a cooling option for custom differential lubrication systems.

• Power Steering Fluid Cooling: Can help manage heat in appropriately configured hydraulic steering systems.

• Corrosion or Physical Damage: Replaces deteriorated cooling components with a durable bar/plate assembly.

• High-Flow Plumbing Requirements: Large M22 x 1.5 ports allow compatibility with appropriately configured high-flow AN fittings.

• Temperature Monitoring Upgrades: Auxiliary 1/8-inch NPT ports provide options for compatible fluid temperature sensors.

Installation Notes

1. Verify Application Requirements: Confirm that the CSF 8371 is suitable for the intended fluid, operating temperature, pressure, and cooling capacity.

2. Measure Available Installation Space: Ensure sufficient clearance for the cooler's 12-inch overall length, 9.85-inch height, and 2.36-inch width.

3. Select a Suitable Mounting Location: Choose an area with adequate airflow and protection from excessive physical contact.

4. Plan Fluid Line Routing: Determine the appropriate inlet and outlet hose routing before installing the cooler.

5. Verify Connection Sizes: Confirm compatibility with the M22 x 1.5 threaded fluid connections.

6. Select Appropriate Adapter Fittings: Use fittings compatible with the cooler's threads, sealing design, and intended hose size.

7. Inspect Auxiliary Ports: Identify the four 1/8-inch NPT ports and determine whether they will be used for sensors, bleeding, or plugs.

8. Seal Unused Ports: Install suitable plugs using a sealing method appropriate for the threads and operating fluid.

9. Fabricate Mounting Brackets: Design brackets compatible with the M8 x 1.25 threaded mounting provisions.

10. Support the Cooler Properly: Ensure the cooler is securely mounted without excessive stress on the end tanks or fluid connections.

11. Confirm Mounting Orientation: Position the cooler to provide appropriate airflow, fluid routing, and bleeding capability.

12. Install Fluid Lines: Route compatible hoses away from exhaust components, moving suspension parts, and sharp edges.

13. Protect Against Abrasion: Use suitable hose protection and support where fluid lines pass near body panels or other components.

14. Verify Fitting Tightness: Follow the fitting manufacturer's recommended installation procedures and torque specifications.

15. Account for Additional Fluid Capacity: Include the cooler's approximately 1.5-liter capacity when calculating the system's total fluid volume.

16. Fill the Cooling System: Add the appropriate fluid according to the vehicle or system manufacturer's recommendations.

17. Prime the System: Follow the appropriate procedure to ensure fluid circulation before subjecting the system to operating loads.

18. Bleed Trapped Air: Remove trapped air using suitable bleeding procedures for the application.

19. Check for Leaks: Inspect all connections, fittings, and auxiliary ports before normal operation.

20. Monitor Operating Temperatures: Confirm that the completed system maintains appropriate fluid temperatures.

21. Reinspect After Initial Operation: Check mounting hardware, fluid connections, and hose routing after several operating cycles.

22. Professional Installation Recommended: Custom fluid-cooling systems may require fabrication and specialized plumbing knowledge.

Important: The CSF 8371 is a universal custom-fit component and is not supplied as a complete vehicle-specific oil cooler kit. Installation may require additional fittings, hoses, brackets, sensors, and other cooling system components.

For engine oil applications, verify whether a thermostatic oil sandwich plate, remote oil filter adapter, or other appropriate oil-routing system is required.

What's Included

• (1) CSF Universal Large Single-Pass High-Performance Oil Cooler (8371)

• Integrated Aero-Flow Bar/Plate Cooling Core

• Integrated TIG-Welded End Tanks

• Integrated M22 x 1.5 Inlet and Outlet Connections

• Integrated Four 1/8-Inch NPT Auxiliary Ports

• Integrated M8 x 1.25 Mounting Provisions

Note: This listing is for the oil cooler assembly. AN adapter fittings, hoses, mounting brackets, thermostatic adapters, temperature sensors, pumps, and other application-specific components should be purchased separately as required. Verify whether auxiliary port plugs or other small hardware are supplied before installation.

Upgrade your vehicle's cooling capabilities with the CSF Universal Large Single-Pass High-Performance Oil Cooler (8371), engineered to deliver efficient heat transfer, exceptional durability, and versatile custom installation options.

Featuring a large Aero-Flow bar/plate core, TIG-welded end tanks, M22 x 1.5 fluid connections, four auxiliary 1/8-inch NPT ports, 1.5-liter fluid capacity, and satin black protective finish, this universal cooler provides a premium solution for demanding engine oil, transmission, differential, and other compatible fluid-cooling applications.

Whether building a turbocharged K-Series Honda, upgrading a high-performance Acura, or fabricating a custom motorsport cooling system, the CSF 8371 delivers the advanced engineering, cooling performance, and rugged construction expected from CSF.