BMW E46 M3 (S54) triple pass radiator, CSF 84-3139

CSF 84-3139 aluminium radiator for the E46 M3 with S54 engine. Triple pass flow and two-row B-tube core give real track-day cooling headroom without compromising daily drivability.

• Direct-fit replacement: uses factory shrouding, hoses and mounting points
• Triple pass design forces coolant through the core three times for consistent thermal control
• B-tube core with louvered fins delivers 15% more heat rejection than stock
• Full coolant system bleed required after installation

Engineered for fast road and track day use - not a stopgap for overheating, but a measured upgrade for drivers who push their S54 hard.