Audi S4 (B5) CSF Performance Aluminium Radiator Upgrade

CSF Performance Aluminium Radiator Upgrade for Audi S4 B5

CSF High Performance Engine Water Cooling All-Aluminium Radiator upgrade, ideal for use in high horsepower builds on street or track to lower coolant temperatures.

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 aluminium 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.

Direct Replacement, Plug and Play

2-Row 42mm Core (Dual Core) Featuring CSF's Exclusive B-Tube Technology

Core Features an Ultra-Efficient Fin with 6.5mm Fin Height and Multi-Louvered Design for Maximum Surface Area Contact

All-Aluminum Race Style Drain Plug

This item will fit Vehicles with the following Engine Codes:

Audi A4 / S4 / Avant / quattro - AJK (230) APB (254)

Replaces Genuine VAG Part Numbers:

8D0121251AN - 8D0121251 AN - 8D0 121 251 AN
8D0121251AP - 8D0121251 AP - 8D0 121 251 AP