Heat Exchanger, CSF Triple-Pass - B46/B58

This is a high-performance front heat exchanger for the B46, B48, and B58 engines found in 2016-2020 F22 230i/M240i, F30 330i/340i, and F32 430i/440i models. The heat exchanger sits in front of the main radiator and is used exclusively for the water:air intercooler in the intake manifold.

This heat exchanger uses CSF's Triple-Pass flow layout to give 3 times the surface area for cooling than the standard heat exchanger (which BMW calls a radiator). Instead of one pass through the radiator core, coolant now makes three passes with cooling air flowing around it. CSF's exclusive B-Tube design is also used for even greater surface area than standard tube. The Triple-Pass layout kept intake air temps stable while the stock heat exchanger caused temps to rise 15% in testing.

The CSF B46/B58 heat exchanger is a direct, drop-in upgrade for the stock cooler, even with the original auto transmission cooler in front. The entire radiator is aluminum, even the end tanks. All of the factory hoses and mounts are re-used and no modification is needed. The CSF even comes with its own rock guard just like the factory piece. All connections are CNC machined and TIG welded.

All CSF radiators receive design and development in the USA with additional wind tunnel, vibration, thermal cycle, burst pressure, and salt spray testing done at their production facilities in Southeast Asia. During manufacturing, radiators are individually tested for leaks and receive a 30-point inspection prior to shipping. CSF is an OE supplier to several manufacturers as well as providing private-label products for other radiator brands. CSF radiators have a two year warranty.

Select from a polished or stealthy black finish.

Notice of Emissions Non-Compliance. This cooler is part of the intake system and the vehicle's emissions equipment. Removing, disabling, or altering emissions equipment on a pollution-controlled road vehicle is illegal. Installing devices or software that trick, disable, or modify emissions controls and monitors on a pollution-controlled road vehicle is also illegal. This product is not legal for sale or use in California on any pollution controlled motor vehicle.

BMW Fitments:

2 Series
F22 / F23 (2016-2020) > 230i
F22 / F23 (2016-2020) > 230i xDrive
F22 / F23 (2016-2020) > M240i
F22 / F23 (2016-2020) > M240i xDrive
3 Series
F30 / F31 / F34 (2016-2019) > 330i
F30 / F31 / F34 (2016-2019) > 330i xDrive
F30 / F34 (2016-2019) > 340i
F30 / F34 (2016-2019) > 340i xDrive
4 Series
F32 / F33 / F36 (2016-2020) > 430i
F32 / F33 / F36 (2016-2020) > 430i xDrive
F32 / F33 / F36 (2016-2020) > 440i
F32 / F33 / F36 (2016-2020) > 440i xDrive