CSF BMW N55 M2/M135I/M235I/335I/435I (F2X/F3X/F87) High-Performance Radiator

Keep temperatures consistently low and prevent heat soak during prolonged fast driving with CSF's High-Performance Radiator, purpose-built for the N55-powered M2, M135i, M235i, 335i, and 435i. The 2-row, 42mm core uses CSF's exclusive B-Tube technology - rather than a regular oval "O"-shaped tube, a specially engineered "B"-shaped tube is carefully formed and brazed over the seam, increasing heat transfer surface area by approximately 15% over regular tubes while allowing for thinner, lighter, more efficient aluminium construction.

Paired with 6.5mm tall, ultra-efficient multi-louvered fins for maximum surface area contact, the radiator features CNC-machined quick-connect inlet/outlet connections and all auxiliary connections, along with CNC-machined brackets and fittings for a superb, durable fit. An all-aluminium race-style drain plug and a genuine one-hour hand-polished mirror finish round out the build quality. It's a true drop-in fit, accepting all OEM attaching components - quick-connect hoses, AC condenser, mounting brackets, and fan shroud - with every unit individually leak tested and given a 30-point inspection before shipping.

Why Choose This Radiator

• CSF's exclusive B-Tube core technology - ~15% more heat transfer surface area than regular tubes
• 6.5mm multi-louvered fins - maximised surface area for efficient heat rejection
• CNC-machined fittings, brackets, and race-style drain plug - genuine durability and fit precision
• Hand-polished mirror finish - premium presentation alongside the performance upgrade
• True drop-in fit - accepts all OEM attaching components, no modification required
• Individually leak tested with 30-point inspection - genuine quality control before shipping

Compatibility

• BMW F87 M2 (N55)
• BMW F20/F21 M135i (N55)
• BMW F22/F23 M235i (N55)
• BMW F30/F31/F34 335i (N55)
• BMW F32/F33/F36 435i (N55)

Fitment note: the thicker core tightens tolerances slightly between the expansion tank and accessory belt - not a fitment issue, but worth being aware of during installation.

Part Number

• Replaces OEM part #17118672103 (manual) / #17118672104 (automatic)