The original OEM B58 heat exchanger is a 1-row unit that is 27mm thick. In comparison, CSF has used its industry-exclusive world's largest 2-row core (68mm) with CSF's B-Tube technology. A unique tank design allows the larger CSF core to still fit into the OEM cooling system housing. Another critical feature of the CSF BMW B58 high-performance heat exchanger is its unique triple-pass flow design. The water traveling through the upgraded heat exchanger flows through the radiator three times before exiting the cooler and flowing back into the manifold charge cooler. This ensures that the outlet water temperature of the heat exchanger is the absolute lowest it can be. The OEM design, as well as more expensive aftermarket designs, all have single-pass flow structures.
Brand: CSF Race
Part: Aluminum Heat Exchanger Kit with Rock Guard
Fitment:
2017-2021 BMW B58 / B48 - Please view compatability chart.
Part Number: 8131
Features:
Core Size: 524mm Length x 478mm Height x 69mm Wide
Replaces OEM Part Number: 17118741830
68mm 2-Row Core with CSF's B-Tube Technology (World's Largest 2-Row Core)
6.5mm Multi-Louvered Fin Height
Triple-Pass Flow Design
Included Detachable Rock Guard
OEM CNC Machined Mounting Location Pins and Brackets
Direct Plug-and-Play Design, Including CNC Machined "Quick Connect" Inlet/Outlet Water Fittings
No Modifications Needed to Install
1-Hour "Mirror Finish" Hand Polish
Warranty: 2 Year Limited Warranty

| Brand | CSF |
| Type | Intercooler |
| Features | 100% Leak Tested |
| Features | High Heat Resistant |
| Items Included | Heat Exchanger |
| Items Included | Rock Guard |
| Color | Polished |
| Manufacturer Part Number | 8131 |
| Performance Part | Yes |
| Manufacturer Warranty | 1 Year |
| California Prop 65 Warning | Applies |
| Material | Aluminum |
| Mounting Style | Bolt-On |
| MPN | 8131 |