CSF Triple Pass Radiator — BMW M3 (E9X)

All-aluminum triple-pass radiator for the S65 V8-powered E90/E92/E93 M3. Coolant crosses the core three times before exiting, raising heat rejection well above the factory unit.

Why It Matters

Rising coolant temperature is one of the few known weak points on the E9x M3 under sustained load — the V8 makes real heat, and the factory cooling package was sized for street use.

Direct fit, no modification required.