CSF 8131B BMW 2016-2021 2/3/4-Series Front Mount Triple-Pass Heat Exchanger with Rock Guard - Black

Fits select 2016-2021 BMW 230i, 330e, 330i, 340i, 430i, 440i, and M240i (B48/B58 Engines).

The CSF 8131B High-Performance Heat Exchanger is engineered to address the thermal limitations of the factory BMW B48 and B58 cooling systems. While the OEM unit utilizes a single-row 27mm core, CSF employs a massive 68mm 2-row core—the largest available for this platform—utilizing proprietary B-Tube technology for maximum surface area and heat dissipation. This design significantly lowers outlet water temperatures before they reach the manifold charge cooler, maintaining lower intake air temperatures during spirited driving or track use.

A critical upgrade over both OEM and standard aftermarket coolers is the triple-pass flow design. This configuration forces coolant to traverse the radiator core three times before exiting, ensuring the lowest possible fluid temperatures. This unit is a direct plug-and-play replacement for OEM part number 17118741830 and requires no modifications for installation.

• 68mm 2-row core featuring CSF B-Tube Technology
• Triple-pass flow design for maximum cooling efficiency
• 6.5mm multi-louvered fin height for optimized airflow
• CNC-machined "Quick Connect" inlet/outlet water fittings
• CNC-machined mounting pins and brackets for factory-like fitment
• Includes detachable mesh rock guard for core protection
• Semi-gloss black finish
• Core Dimensions: 524mm L x 478mm H x 69mm W
• Replaces OEM Part Number: 17118741830