CSF Audi S4/S5, A4/A5, A6, A7, Q5 & SQ5 High Performance Radiator

Part # 7091
  • Sale
  • $649.00
  • Regular price $699.00

CSF’s High-Performance 2-Row Radiator is complete with precise CNC machined fittings and brackets to allow ease of installation in the complex plastic housing system. It also includes an OEM-style wire harness bracket system to secure the harness that runs across the top of the radiator In addition to CSF’s high-performance radiator core design, CSF has added an upgraded plate-type transmission oil cooler to the left side tank for improved transmission cooling in vehicles with automatic transmissions (comes pre-plugged for use in manual transmission vehicles).

CSF Technology

CSF manufactures the most advanced and efficient radiator cores in the industry by using innovative tube and fin technologies with industry leading testing methods to maximize airflow and heat dissipation. These techniques allow CSF to stay ahead of the pack when it comes to radiator technology! “B-Tube” technology – Unlike a regular oval shape “O” type radiator tube, CSF uses a specially engineered tube in a shape of a “B”. These “B-tubes” are carefully formed and then brazed over the seam to seal. CSF is able to use thinner and lighter aluminum material (better cooling efficiency) because this design is actually stronger than normal “O” shape tubes that are welded. The design (inlet in the middle of tube that is seam brazed) increases the heat transfer surface area of the tubes by approximately 15% over regular tubes. You get the efficiency of 2 smaller tubes vs. 1 large tube within the same space criteria. With “B-tubes” you are able to get “dual liquid laminar flow.” High Efficiency Multi Louvered Fin – CSF uses ultra efficient multi louvered fins that are carefully and precisely aligned to maximize airflow through each radiator core. Fin specifications are carefully measured and calculated for each application, and tested for maximum heat rejection efficiency in our wind-tunnel lab. Each CSF high quality radiator is completed with an industry leading 1 hour, hand polished “Show-Stopper™ mirror finish.” Our hand polishing tools and techniques in our new polishing center located at the end of the production line ensures that every CSF cooling system looks just as good as it performs.


  • 2-Row 42mm High-Performance Core Featuring CSF’s B-Tube Technology
  • Core Features Ultra Efficient 6.5mm Tall Fins with a Multi-Louvered Design for Maximum Surface Area Contact
  • 100% All-Aluminum TIG-Welded Construction
  • CNC Machined Mounting Brackets and OEM Style “Quick Connect” Inlet/Outlet
  • Integrated High-Performance Transmission Oil Cooler for Both Automatic and Manual Transmissions
  • Integrated OEM Style Wire Harness Brackets
  • True “Drop-in Fit” Requires No Modifications to Install
  • Individually Leak and Pressure Tested
  • 1 Hour “Mirror Finish” Hand Polish
  • 2 Year Limited Warranty


  • 2010-16 Audi (B8) S4
  • 2009-14 Audi (B8) A4 Quattro
  • 2010-14 Audi (B8) S5
  • 2008-16 Audi (B8) A5
  • 2008-14 Audi (B8) A5 Quattro
  • 2010-13 Audi A6
  • 2016 Audi A6
  • 2012-15 Audi A6 Quattro
  • 2016 Audi A7
  • 2012-15 Audi A7 Quattro
  • 2009-17 Audi Q5
  • 2014-17 Audi SQ5
  • 2015-18 Porsche Macan S & GTS
  • OEM #
    • Automatic: 8K0-121-251-AL
    • Manual: 8K0-121-251-H